21901206724 has 24 divisors (see below), whose sum is σ = 38586128000. Its totient is φ = 10876653216.

The previous prime is 21901206713. The next prime is 21901206739. The reversal of 21901206724 is 42760210912.

It is a self number, because there is not a number n which added to its sum of digits gives 21901206724.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2192389 + ... + 2202355.

Almost surely, 2^21901206724 is an apocalyptic number.

It is an amenable number.

21901206724 is a deficient number, since it is larger than the sum of its proper divisors (16684921276).

21901206724 is a wasteful number, since it uses less digits than its factorization.

21901206724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13627 (or 13625 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The spelling of 21901206724 in words is "twenty-one billion, nine hundred one million, two hundred six thousand, seven hundred twenty-four".