21654734788 has 12 divisors (see below), whose sum is σ = 38107495440. Its totient is φ = 10766878952.

The previous prime is 21654734771. The next prime is 21654734791. The reversal of 21654734788 is 88743745612.

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, 15121306 + ... + 15122737.

It is an arithmetic number, because the mean of its divisors is an integer number (3175624620).

Almost surely, 2^21654734788 is an apocalyptic number.

It is an amenable number.

21654734788 is a deficient number, since it is larger than the sum of its proper divisors (16452760652).

21654734788 is a wasteful number, since it uses less digits than its factorization.

21654734788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30244226 (or 30244224 counting only the distinct ones).

The product of its digits is 9031680, while the sum is 55.

The spelling of 21654734788 in words is "twenty-one billion, six hundred fifty-four million, seven hundred thirty-four thousand, seven hundred eighty-eight".