55117861 has 2 divisors, whose sum is σ = 55117862. Its totient is φ = 55117860.

The previous prime is 55117819. The next prime is 55117891. The reversal of 55117861 is 16871155.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 42380100 + 12737761 = 6510^2 + 3569^2 .

It is a cyclic number.

It is not a de Polignac number, because 55117861 - 2²³ = 46729253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55117801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27558930 + 27558931.

It is an arithmetic number, because the mean of its divisors is an integer number (27558931).

Almost surely, 2^55117861 is an apocalyptic number.

It is an amenable number.

55117861 is a deficient number, since it is larger than the sum of its proper divisors (1).

55117861 is an equidigital number, since it uses as much as digits as its factorization.

55117861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8400, while the sum is 34.

The square root of 55117861 is about 7424.1404216246. The cubic root of 55117861 is about 380.5667006174.

The spelling of 55117861 in words is "fifty-five million, one hundred seventeen thousand, eight hundred sixty-one".