21551669752 has 32 divisors (see below), whose sum is σ = 42750000000. Its totient is φ = 10157371488.

The previous prime is 21551669747. The next prime is 21551669759. The reversal of 21551669752 is 25796615512.

It is a junction number, because it is equal to n+sod(n) for n = 21551669696 and 21551669705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21551669759) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 326002 + ... + 386497.

It is an arithmetic number, because the mean of its divisors is an integer number (1335937500).

Almost surely, 2^21551669752 is an apocalyptic number.

It is an amenable number.

21551669752 is a deficient number, since it is larger than the sum of its proper divisors (21198330248).

21551669752 is a wasteful number, since it uses less digits than its factorization.

21551669752 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 712723 (or 712719 counting only the distinct ones).

The product of its digits is 1134000, while the sum is 49.

The spelling of 21551669752 in words is "twenty-one billion, five hundred fifty-one million, six hundred sixty-nine thousand, seven hundred fifty-two".