21753551838 has 32 divisors (see below), whose sum is σ = 44063663616. Its totient is φ = 7158552768.

The previous prime is 21753551819. The next prime is 21753551843. The reversal of 21753551838 is 83815535712.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 693306 + ... + 724002.

It is an arithmetic number, because the mean of its divisors is an integer number (1376989488).

Almost surely, 2^21753551838 is an apocalyptic number.

21753551838 is an abundant number, since it is smaller than the sum of its proper divisors (22310111778).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21753551838 is a wasteful number, since it uses less digits than its factorization.

21753551838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32208.

The product of its digits is 1008000, while the sum is 48.

The spelling of 21753551838 in words is "twenty-one billion, seven hundred fifty-three million, five hundred fifty-one thousand, eight hundred thirty-eight".