21621960396 has 48 divisors (see below), whose sum is σ = 57571997280. Its totient is φ = 7012526400.

The previous prime is 21621960377. The next prime is 21621960403. The reversal of 21621960396 is 69306912612.

21621960396 is a `hidden beast` number, since 2 + 16 + 21 + 9 + 603 + 9 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2701455 + ... + 2709446.

It is an arithmetic number, because the mean of its divisors is an integer number (1199416610).

Almost surely, 2^21621960396 is an apocalyptic number.

It is an amenable number.

21621960396 is an abundant number, since it is smaller than the sum of its proper divisors (35950036884).

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

21621960396 is a wasteful number, since it uses less digits than its factorization.

21621960396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5410951 (or 5410943 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The spelling of 21621960396 in words is "twenty-one billion, six hundred twenty-one million, nine hundred sixty thousand, three hundred ninety-six".