157631 has 4 divisors (see below), whose sum is σ = 158472. Its totient is φ = 156792.

The previous prime is 157627. The next prime is 157637. The reversal of 157631 is 136751.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 157631 - 2² = 157627 is a prime.

It is a super-2 number, since 2×157631² = 49695064322, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 157597 and 157606.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (157637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5 + ... + 561.

It is an arithmetic number, because the mean of its divisors is an integer number (39618).

2¹⁵⁷⁶³¹ is an apocalyptic number.

157631 is a deficient number, since it is larger than the sum of its proper divisors (841).

157631 is an equidigital number, since it uses as much as digits as its factorization.

157631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 840.

The product of its digits is 630, while the sum is 23.

The square root of 157631 is about 397.0277068417. The cubic root of 157631 is about 54.0190833330.

The spelling of 157631 in words is "one hundred fifty-seven thousand, six hundred thirty-one".