21920985396 has 48 divisors (see below), whose sum is σ = 56841523200. Its totient is φ = 7305794496.

The previous prime is 21920985389. The next prime is 21920985397. The reversal of 21920985396 is 69358902912.

It is a happy number.

21920985396 is a `hidden beast` number, since 2 + 19 + 2 + 0 + 98 + 539 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21920985397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 852301 + ... + 877643.

It is an arithmetic number, because the mean of its divisors is an integer number (1184198400).

Almost surely, 2^21920985396 is an apocalyptic number.

It is an amenable number.

21920985396 is an abundant number, since it is smaller than the sum of its proper divisors (34920537804).

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

21920985396 is a wasteful number, since it uses less digits than its factorization.

21920985396 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33365 (or 33357 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The spelling of 21920985396 in words is "twenty-one billion, nine hundred twenty million, nine hundred eighty-five thousand, three hundred ninety-six".