21551545332120 has 64 divisors (see below), whose sum is σ = 64658689492320. Its totient is φ = 5746718444544.

The previous prime is 21551545332073. The next prime is 21551545332131. The reversal of 21551545332120 is 2123354515512.

It is a super-2 number, since 2×21551545332120² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3705109 + ... + 7538628.

Almost surely, 2^{21551545332120} is an apocalyptic number.

21551545332120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21551545332120 is an abundant number, since it is smaller than the sum of its proper divisors (43107144160200).

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

21551545332120 is a wasteful number, since it uses less digits than its factorization.

21551545332120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11259724 (or 11259720 counting only the distinct ones).

The product of its (nonzero) digits is 180000, while the sum is 39.

Adding to 21551545332120 its reverse (2123354515512), we get a palindrome (23674899847632).

The spelling of 21551545332120 in words is "twenty-one trillion, five hundred fifty-one billion, five hundred forty-five million, three hundred thirty-two thousand, one hundred twenty".