61566157 has 2 divisors, whose sum is σ = 61566158. Its totient is φ = 61566156.

The previous prime is 61566139. The next prime is 61566179. The reversal of 61566157 is 75166516.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 59197636 + 2368521 = 7694^2 + 1539^2 .

It is a cyclic number.

It is not a de Polignac number, because 61566157 - 2²³ = 53177549 is a prime.

It is a pancake number, because a pancake can be divided into 61566157 parts by 11096 straight cuts.

It is equal to p_3649429 and since 61566157 and 3649429 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61566107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30783078 + 30783079.

It is an arithmetic number, because the mean of its divisors is an integer number (30783079).

Almost surely, 2^61566157 is an apocalyptic number.

It is an amenable number.

61566157 is a deficient number, since it is larger than the sum of its proper divisors (1).

61566157 is an equidigital number, since it uses as much as digits as its factorization.

61566157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37800, while the sum is 37.

The square root of 61566157 is about 7846.4104531945. The cubic root of 61566157 is about 394.8638253024.

The spelling of 61566157 in words is "sixty-one million, five hundred sixty-six thousand, one hundred fifty-seven".