55188333721 has 2 divisors, whose sum is σ = 55188333722. Its totient is φ = 55188333720.

The previous prime is 55188333709. The next prime is 55188333769. The reversal of 55188333721 is 12733388155.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 53599195225 + 1589138496 = 231515^2 + 39864^2 .

It is a cyclic number.

It is not a de Polignac number, because 55188333721 - 2⁷ = 55188333593 is a prime.

It is not a weakly prime, because it can be changed into another prime (55188333121) 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 as a sum of consecutive naturals, namely, 27594166860 + 27594166861.

It is an arithmetic number, because the mean of its divisors is an integer number (27594166861).

Almost surely, 2^55188333721 is an apocalyptic number.

It is an amenable number.

55188333721 is a deficient number, since it is larger than the sum of its proper divisors (1).

55188333721 is an equidigital number, since it uses as much as digits as its factorization.

55188333721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 604800, while the sum is 46.

The spelling of 55188333721 in words is "fifty-five billion, one hundred eighty-eight million, three hundred thirty-three thousand, seven hundred twenty-one".