55621633221 has 48 divisors (see below), whose sum is σ = 100720733568. Its totient is φ = 28734652800.

The previous prime is 55621633187. The next prime is 55621633229. The reversal of 55621633221 is 12233612655.

55621633221 is a `hidden beast` number, since 5 + 5 + 621 + 6 + 3 + 3 + 2 + 21 = 666.

It is not a de Polignac number, because 55621633221 - 2⁶ = 55621633157 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55621633229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 96286 + ... + 347151.

It is an arithmetic number, because the mean of its divisors is an integer number (2098348616).

Almost surely, 2^55621633221 is an apocalyptic number.

It is an amenable number.

55621633221 is a deficient number, since it is larger than the sum of its proper divisors (45099100347).

55621633221 is a wasteful number, since it uses less digits than its factorization.

55621633221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 443642 (or 443639 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The spelling of 55621633221 in words is "fifty-five billion, six hundred twenty-one million, six hundred thirty-three thousand, two hundred twenty-one".