163631257 has 2 divisors, whose sum is σ = 163631258. Its totient is φ = 163631256.

The previous prime is 163631243. The next prime is 163631261. The reversal of 163631257 is 752136361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 146192281 + 17438976 = 12091^2 + 4176^2 .

It is an emirp because it is prime and its reverse (752136361) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-163631257 is a prime.

It is not a weakly prime, because it can be changed into another prime (163631557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 81815628 + 81815629.

It is an arithmetic number, because the mean of its divisors is an integer number (81815629).

Almost surely, 2^163631257 is an apocalyptic number.

It is an amenable number.

163631257 is a deficient number, since it is larger than the sum of its proper divisors (1).

163631257 is an equidigital number, since it uses as much as digits as its factorization.

163631257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 34.

The square root of 163631257 is about 12791.8433777153. The cubic root of 163631257 is about 546.9598177756.

The spelling of 163631257 in words is "one hundred sixty-three million, six hundred thirty-one thousand, two hundred fifty-seven".