21156128104392 has 48 divisors (see below), whose sum is σ = 57298078855680. Its totient is φ = 7052014159200.

The previous prime is 21156128104361. The next prime is 21156128104429. The reversal of 21156128104392 is 29340182165112.

21156128104392 is a `hidden beast` number, since 2 + 1 + 1 + 561 + 2 + 81 + 0 + 4 + 3 + 9 + 2 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24794217 + ... + 25633287.

It is an arithmetic number, because the mean of its divisors is an integer number (1193709976160).

Almost surely, 2^{21156128104392} is an apocalyptic number.

It is an amenable number.

21156128104392 is an abundant number, since it is smaller than the sum of its proper divisors (36141950751288).

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

21156128104392 is a wasteful number, since it uses less digits than its factorization.

21156128104392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1189274 (or 1189267 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 21156128104392 in words is "twenty-one trillion, one hundred fifty-six billion, one hundred twenty-eight million, one hundred four thousand, three hundred ninety-two".