21703725531 has 12 divisors (see below), whose sum is σ = 31352212008. Its totient is φ = 14468049024.

The previous prime is 21703725523. The next prime is 21703725577. The reversal of 21703725531 is 13552730712.

It is a happy number.

21703725531 is a `hidden beast` number, since 2 + 1 + 70 + 37 + 2 + 553 + 1 = 666.

It is not a de Polignac number, because 21703725531 - 2³ = 21703725523 is a prime.

It is a super-2 number, since 2×21703725531² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21703725731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 43531 + ... + 212843.

It is an arithmetic number, because the mean of its divisors is an integer number (2612684334).

Almost surely, 2^21703725531 is an apocalyptic number.

21703725531 is a deficient number, since it is larger than the sum of its proper divisors (9648486477).

21703725531 is a wasteful number, since it uses less digits than its factorization.

21703725531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183562 (or 183559 counting only the distinct ones).

The product of its (nonzero) digits is 44100, while the sum is 36.

The spelling of 21703725531 in words is "twenty-one billion, seven hundred three million, seven hundred twenty-five thousand, five hundred thirty-one".