21752972738 has 32 divisors (see below), whose sum is σ = 40519741440. Its totient is φ = 8547126480.

The previous prime is 21752972701. The next prime is 21752972767. The reversal of 21752972738 is 83727925712.

It is a self number, because there is not a number n which added to its sum of digits gives 21752972738.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1310756 + ... + 1327247.

It is an arithmetic number, because the mean of its divisors is an integer number (1266241920).

Almost surely, 2^21752972738 is an apocalyptic number.

21752972738 is a deficient number, since it is larger than the sum of its proper divisors (18766768702).

21752972738 is a wasteful number, since it uses less digits than its factorization.

21752972738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2638062.

The product of its digits is 2963520, while the sum is 53.

The spelling of 21752972738 in words is "twenty-one billion, seven hundred fifty-two million, nine hundred seventy-two thousand, seven hundred thirty-eight".