55011109921 has 2 divisors, whose sum is σ = 55011109922. Its totient is φ = 55011109920.

The previous prime is 55011109919. The next prime is 55011109943. The reversal of 55011109921 is 12990111055.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48801669921 + 6209440000 = 220911^2 + 78800^2 .

It is a cyclic number.

It is not a de Polignac number, because 55011109921 - 2¹ = 55011109919 is a prime.

Together with 55011109919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (55011109991) 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, 27505554960 + 27505554961.

It is an arithmetic number, because the mean of its divisors is an integer number (27505554961).

Almost surely, 2^55011109921 is an apocalyptic number.

It is an amenable number.

55011109921 is a deficient number, since it is larger than the sum of its proper divisors (1).

55011109921 is an equidigital number, since it uses as much as digits as its factorization.

55011109921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4050, while the sum is 34.

The spelling of 55011109921 in words is "fifty-five billion, eleven million, one hundred nine thousand, nine hundred twenty-one".