187631 has 2 divisors, whose sum is σ = 187632. Its totient is φ = 187630.

The previous prime is 187597. The next prime is 187633. The reversal of 187631 is 136781.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187631 is a prime.

It is a super-2 number, since 2×187631² = 70410784322, which contains 22 as substring.

Together with 187633, it forms a pair of twin primes.

It is a Chen prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 187631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187633) 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 as a sum of consecutive naturals, namely, 93815 + 93816.

It is an arithmetic number, because the mean of its divisors is an integer number (93816).

2¹⁸⁷⁶³¹ is an apocalyptic number.

187631 is a deficient number, since it is larger than the sum of its proper divisors (1).

187631 is an equidigital number, since it uses as much as digits as its factorization.

187631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1008, while the sum is 26.

The square root of 187631 is about 433.1639412509. The cubic root of 187631 is about 57.2490385860.

It can be divided in two parts, 187 and 631, that added together give a palindrome (818).

The spelling of 187631 in words is "one hundred eighty-seven thousand, six hundred thirty-one".