155657 has 2 divisors, whose sum is σ = 155658. Its totient is φ = 155656.

The previous prime is 155653. The next prime is 155663. The reversal of 155657 is 756551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 121801 + 33856 = 349^2 + 184^2 .

It is a cyclic number.

It is not a de Polignac number, because 155657 - 2² = 155653 is a prime.

It is not a weakly prime, because it can be changed into another prime (155653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77828 + 77829.

It is an arithmetic number, because the mean of its divisors is an integer number (77829).

2¹⁵⁵⁶⁵⁷ is an apocalyptic number.

It is an amenable number.

155657 is a deficient number, since it is larger than the sum of its proper divisors (1).

155657 is an equidigital number, since it uses as much as digits as its factorization.

155657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5250, while the sum is 29.

The square root of 155657 is about 394.5339022188. The cubic root of 155657 is about 53.7926432822.

The spelling of 155657 in words is "one hundred fifty-five thousand, six hundred fifty-seven".