21955152555 has 96 divisors (see below), whose sum is σ = 45877478400. Its totient is φ = 9488399616.

The previous prime is 21955152553. The next prime is 21955152589. The reversal of 21955152555 is 55525155912.

21955152555 is a `hidden beast` number, since 2 + 1 + 95 + 5 + 1 + 5 + 2 + 555 = 666.

It is not a de Polignac number, because 21955152555 - 2¹ = 21955152553 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 21955152555.

It is not an unprimeable number, because it can be changed into a prime (21955152553) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3042762 + ... + 3049968.

It is an arithmetic number, because the mean of its divisors is an integer number (477890400).

Almost surely, 2^21955152555 is an apocalyptic number.

21955152555 is an abundant number, since it is smaller than the sum of its proper divisors (23922325845).

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

21955152555 is a wasteful number, since it uses less digits than its factorization.

21955152555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7753 (or 7750 counting only the distinct ones).

The product of its digits is 562500, while the sum is 45.

The spelling of 21955152555 in words is "twenty-one billion, nine hundred fifty-five million, one hundred fifty-two thousand, five hundred fifty-five".