21474234956 has 18 divisors (see below), whose sum is σ = 38220865620. Its totient is φ = 10554025912.

The previous prime is 21474234919. The next prime is 21474235001. The reversal of 21474234956 is 65943247412.

It is a super-2 number, since 2×21474234956² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21474234956.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2246435 + ... + 2255973.

Almost surely, 2^21474234956 is an apocalyptic number.

It is an amenable number.

21474234956 is a deficient number, since it is larger than the sum of its proper divisors (16746630664).

21474234956 is an frugal number, since it uses more digits than its factorization.

21474234956 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19141 (or 9600 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 47.

The spelling of 21474234956 in words is "twenty-one billion, four hundred seventy-four million, two hundred thirty-four thousand, nine hundred fifty-six".