21312656360555 has 64 divisors (see below), whose sum is σ = 30164141629440. Its totient is φ = 14155843046400.

The previous prime is 21312656360549. The next prime is 21312656360591. The reversal of 21312656360555 is 55506365621312.

It is a happy number.

It is not a de Polignac number, because 21312656360555 - 2⁶ = 21312656360491 is a prime.

It is a super-2 number, since 2×21312656360555² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 37493510 + ... + 38057700.

It is an arithmetic number, because the mean of its divisors is an integer number (471314712960).

Almost surely, 2^{21312656360555} is an apocalyptic number.

21312656360555 is a deficient number, since it is larger than the sum of its proper divisors (8851485268885).

21312656360555 is a wasteful number, since it uses less digits than its factorization.

21312656360555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 564540.

The product of its (nonzero) digits is 4860000, while the sum is 50.

The spelling of 21312656360555 in words is "twenty-one trillion, three hundred twelve billion, six hundred fifty-six million, three hundred sixty thousand, five hundred fifty-five".