20316631 has 2 divisors, whose sum is σ = 20316632. Its totient is φ = 20316630.

The previous prime is 20316623. The next prime is 20316641. The reversal of 20316631 is 13661302.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20316631 - 2³ = 20316623 is a prime.

It is a super-2 number, since 2×20316631² = 825530990380322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20316641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10158315 + 10158316.

It is an arithmetic number, because the mean of its divisors is an integer number (10158316).

Almost surely, 2^20316631 is an apocalyptic number.

20316631 is a deficient number, since it is larger than the sum of its proper divisors (1).

20316631 is an equidigital number, since it uses as much as digits as its factorization.

20316631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 20316631 is about 4507.3973643334. The cubic root of 20316631 is about 272.8667161023.

Adding to 20316631 its reverse (13661302), we get a palindrome (33977933).

The spelling of 20316631 in words is "twenty million, three hundred sixteen thousand, six hundred thirty-one".