21221355320055 has 128 divisors (see below), whose sum is σ = 41774493450240. Its totient is φ = 10135026478080.

The previous prime is 21221355320047. The next prime is 21221355320063. The reversal of 21221355320055 is 55002355312212.

21221355320055 is a `hidden beast` number, since 2 + 1 + 22 + 13 + 553 + 20 + 0 + 55 = 666.

It is an interprime number because it is at equal distance from previous prime (21221355320047) and next prime (21221355320063).

It is not a de Polignac number, because 21221355320055 - 2³ = 21221355320047 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 83670442 + ... + 83923688.

It is an arithmetic number, because the mean of its divisors is an integer number (326363230080).

Almost surely, 2^{21221355320055} is an apocalyptic number.

21221355320055 is a deficient number, since it is larger than the sum of its proper divisors (20553138130185).

21221355320055 is a wasteful number, since it uses less digits than its factorization.

21221355320055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 254118 (or 254112 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 36.

The spelling of 21221355320055 in words is "twenty-one trillion, two hundred twenty-one billion, three hundred fifty-five million, three hundred twenty thousand, fifty-five".