21703725538 has 16 divisors (see below), whose sum is σ = 35556659424. Its totient is φ = 9853809760.

The previous prime is 21703725523. The next prime is 21703725577. The reversal of 21703725538 is 83552730712.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21703725494 and 21703725503.

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, 556720 + ... + 594427.

It is an arithmetic number, because the mean of its divisors is an integer number (2222291214).

Almost surely, 2^21703725538 is an apocalyptic number.

21703725538 is a deficient number, since it is larger than the sum of its proper divisors (13852933886).

21703725538 is a wasteful number, since it uses less digits than its factorization.

21703725538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1152017.

The product of its (nonzero) digits is 352800, while the sum is 43.

The spelling of 21703725538 in words is "twenty-one billion, seven hundred three million, seven hundred twenty-five thousand, five hundred thirty-eight".