155165557 has 2 divisors, whose sum is σ = 155165558. Its totient is φ = 155165556.

The previous prime is 155165551. The next prime is 155165581. The reversal of 155165557 is 755561551.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 101787921 + 53377636 = 10089^2 + 7306^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155165557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155165551) 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, 77582778 + 77582779.

It is an arithmetic number, because the mean of its divisors is an integer number (77582779).

Almost surely, 2^155165557 is an apocalyptic number.

It is an amenable number.

155165557 is a deficient number, since it is larger than the sum of its proper divisors (1).

155165557 is an equidigital number, since it uses as much as digits as its factorization.

155165557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 131250, while the sum is 40.

The square root of 155165557 is about 12456.5467526117. The cubic root of 155165557 is about 537.3597190793.

The spelling of 155165557 in words is "one hundred fifty-five million, one hundred sixty-five thousand, five hundred fifty-seven".