16631 has 2 divisors, whose sum is σ = 16632. Its totient is φ = 16630.

The previous prime is 16619. The next prime is 16633. The reversal of 16631 is 13661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 16631 - 2⁶ = 16567 is a prime.

It is a super-2 number, since 2×16631² = 553180322, which contains 22 as substring.

Together with 16633, it forms a pair of twin primes.

It is a Chen prime.

It is a nialpdrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8315 + 8316.

It is an arithmetic number, because the mean of its divisors is an integer number (8316).

2¹⁶⁶³¹ is an apocalyptic number.

16631 is a deficient number, since it is larger than the sum of its proper divisors (1).

16631 is an equidigital number, since it uses as much as digits as its factorization.

16631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 108, while the sum is 17.

The square root of 16631 is about 128.9612344854. The cubic root of 16631 is about 25.5254135978.

The spelling of 16631 in words is "sixteen thousand, six hundred thirty-one".