212120828640 has 576 divisors, whose sum is σ = 847780577280. Its totient is φ = 47290060800.

The previous prime is 212120828611. The next prime is 212120828669. The reversal of 212120828640 is 46828021212.

212120828640 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 2 + 0 + 8 + 2 + 8 + 640 = 666.

212120828640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (212120828611) and next prime (212120828669).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 212120828595 and 212120828604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 184292065 + ... + 184293215.

It is an arithmetic number, because the mean of its divisors is an integer number (1471841280).

Almost surely, 2^212120828640 is an apocalyptic number.

212120828640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212120828640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (423890288640).

212120828640 is an abundant number, since it is smaller than the sum of its proper divisors (635659748640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

212120828640 is a wasteful number, since it uses less digits than its factorization.

212120828640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1615 (or 1604 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 36.

Adding to 212120828640 its reverse (46828021212), we get a palindrome (258948849852).

The spelling of 212120828640 in words is "two hundred twelve billion, one hundred twenty million, eight hundred twenty-eight thousand, six hundred forty".