21551586255 has 48 divisors (see below), whose sum is σ = 37671251904. Its totient is φ = 11397603840.

The previous prime is 21551586253. The next prime is 21551586311. The reversal of 21551586255 is 55268515512.

21551586255 is a `hidden beast` number, since 2 + 1 + 5 + 5 + 15 + 8 + 625 + 5 = 666.

It is not a de Polignac number, because 21551586255 - 2¹ = 21551586253 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 21551586255.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21551586253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2753107 + ... + 2760923.

It is an arithmetic number, because the mean of its divisors is an integer number (784817748).

Almost surely, 2^21551586255 is an apocalyptic number.

21551586255 is a deficient number, since it is larger than the sum of its proper divisors (16119665649).

21551586255 is a wasteful number, since it uses less digits than its factorization.

21551586255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8336 (or 8333 counting only the distinct ones).

The product of its digits is 600000, while the sum is 45.

The spelling of 21551586255 in words is "twenty-one billion, five hundred fifty-one million, five hundred eighty-six thousand, two hundred fifty-five".