21357044256 has 24 divisors (see below), whose sum is σ = 56062241424. Its totient is φ = 7119014720.

The previous prime is 21357044237. The next prime is 21357044263. The reversal of 21357044256 is 65244075312.

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×21357044256² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111234510 + ... + 111234701.

It is an arithmetic number, because the mean of its divisors is an integer number (2335926726).

Almost surely, 2^21357044256 is an apocalyptic number.

It is an amenable number.

21357044256 is an abundant number, since it is smaller than the sum of its proper divisors (34705197168).

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

21357044256 is a wasteful number, since it uses less digits than its factorization.

21357044256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222469224 (or 222469216 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 39.

The spelling of 21357044256 in words is "twenty-one billion, three hundred fifty-seven million, forty-four thousand, two hundred fifty-six".