21699645928 has 16 divisors (see below), whose sum is σ = 40689168480. Its totient is φ = 10849201008.

The previous prime is 21699645901. The next prime is 21699645943. The reversal of 21699645928 is 82954699612.

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, 92451 + ... + 227917.

It is an arithmetic number, because the mean of its divisors is an integer number (2543073030).

Almost surely, 2^21699645928 is an apocalyptic number.

It is an amenable number.

21699645928 is a deficient number, since it is larger than the sum of its proper divisors (18989522552).

21699645928 is a wasteful number, since it uses less digits than its factorization.

21699645928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155496 (or 155492 counting only the distinct ones).

The product of its digits is 16796160, while the sum is 61.

The spelling of 21699645928 in words is "twenty-one billion, six hundred ninety-nine million, six hundred forty-five thousand, nine hundred twenty-eight".