21556555712151 has 16 divisors (see below), whose sum is σ = 29319788121984. Its totient is φ = 14082835973024.

The previous prime is 21556555712149. The next prime is 21556555712161. The reversal of 21556555712151 is 15121755565512.

It is a cyclic number.

It is not a de Polignac number, because 21556555712151 - 2¹ = 21556555712149 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21556555712094 and 21556555712103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21556555712101) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81836961 + ... + 82099946.

It is an arithmetic number, because the mean of its divisors is an integer number (1832486757624).

Almost surely, 2^{21556555712151} is an apocalyptic number.

21556555712151 is a deficient number, since it is larger than the sum of its proper divisors (7763232409833).

21556555712151 is a wasteful number, since it uses less digits than its factorization.

21556555712151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163937790.

The product of its digits is 2625000, while the sum is 51.

The spelling of 21556555712151 in words is "twenty-one trillion, five hundred fifty-six billion, five hundred fifty-five million, seven hundred twelve thousand, one hundred fifty-one".