55855861 has 2 divisors, whose sum is σ = 55855862. Its totient is φ = 55855860.

The previous prime is 55855853. The next prime is 55855867. The reversal of 55855861 is 16855855.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34751025 + 21104836 = 5895^2 + 4594^2 .

It is a cyclic number.

It is not a de Polignac number, because 55855861 - 2³ = 55855853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55855867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27927930 + 27927931.

It is an arithmetic number, because the mean of its divisors is an integer number (27927931).

Almost surely, 2^55855861 is an apocalyptic number.

It is an amenable number.

55855861 is a deficient number, since it is larger than the sum of its proper divisors (1).

55855861 is an equidigital number, since it uses as much as digits as its factorization.

55855861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 240000, while the sum is 43.

The square root of 55855861 is about 7473.6778763872. The cubic root of 55855861 is about 382.2577069199.

The spelling of 55855861 in words is "fifty-five million, eight hundred fifty-five thousand, eight hundred sixty-one".