212120640 has 112 divisors (see below), whose sum is σ = 748344960. Its totient is φ = 56563200.

The previous prime is 212120627. The next prime is 212120647. The reversal of 212120640 is 46021212.

212120640 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 20 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (212120647) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3636 + ... + 20915.

Almost surely, 2^212120640 is an apocalyptic number.

212120640 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 212120640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (374172480).

212120640 is an abundant number, since it is smaller than the sum of its proper divisors (536224320).

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

212120640 is a wasteful number, since it uses less digits than its factorization.

212120640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24577 (or 24561 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 212120640 is about 14564.3619839662. The cubic root of 212120640 is about 596.3862787268.

Adding to 212120640 its reverse (46021212), we get a palindrome (258141852).

The spelling of 212120640 in words is "two hundred twelve million, one hundred twenty thousand, six hundred forty".