21650740172 has 12 divisors (see below), whose sum is σ = 37940070840. Its totient is φ = 10810719936.

The previous prime is 21650740159. The next prime is 21650740211. The reversal of 21650740172 is 27104705612.

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, 3659213 + ... + 3665124.

It is an arithmetic number, because the mean of its divisors is an integer number (3161672570).

Almost surely, 2^21650740172 is an apocalyptic number.

It is an amenable number.

21650740172 is a deficient number, since it is larger than the sum of its proper divisors (16289330668).

21650740172 is a wasteful number, since it uses less digits than its factorization.

21650740172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7325080 (or 7325078 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 35.

The spelling of 21650740172 in words is "twenty-one billion, six hundred fifty million, seven hundred forty thousand, one hundred seventy-two".