55815157 has 2 divisors, whose sum is σ = 55815158. Its totient is φ = 55815156.

The previous prime is 55815139. The next prime is 55815191. The reversal of 55815157 is 75151855.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51710481 + 4104676 = 7191^2 + 2026^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55815157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55815127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27907578 + 27907579.

It is an arithmetic number, because the mean of its divisors is an integer number (27907579).

Almost surely, 2^55815157 is an apocalyptic number.

It is an amenable number.

55815157 is a deficient number, since it is larger than the sum of its proper divisors (1).

55815157 is an equidigital number, since it uses as much as digits as its factorization.

55815157 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 35000, while the sum is 37.

The square root of 55815157 is about 7470.9542228553. The cubic root of 55815157 is about 382.1648297744.

The spelling of 55815157 in words is "fifty-five million, eight hundred fifteen thousand, one hundred fifty-seven".