212420340 has 144 divisors (see below), whose sum is σ = 726626880. Its totient is φ = 51480000.

The previous prime is 212420311. The next prime is 212420347. The reversal of 212420340 is 43024212.

212420340 is a `hidden beast` number, since 212 + 420 + 34 + 0 = 666.

212420340 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (212420347) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 63715 + ... + 66965.

It is an arithmetic number, because the mean of its divisors is an integer number (5046020).

Almost surely, 2^212420340 is an apocalyptic number.

212420340 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 212420340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (363313440).

212420340 is an abundant number, since it is smaller than the sum of its proper divisors (514206540).

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

212420340 is a wasteful number, since it uses less digits than its factorization.

212420340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3291 (or 3272 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 212420340 is about 14574.6471655406. The cubic root of 212420340 is about 596.6670196864.

Adding to 212420340 its reverse (43024212), we get a palindrome (255444552).

The spelling of 212420340 in words is "two hundred twelve million, four hundred twenty thousand, three hundred forty".