20713631 has 2 divisors, whose sum is σ = 20713632. Its totient is φ = 20713630.

The previous prime is 20713613. The next prime is 20713657. The reversal of 20713631 is 13631702.

It is a happy number.

Together with previous prime (20713613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20713631 - 2¹⁰ = 20712607 is a prime.

It is a super-2 number, since 2×20713631² = 858109018408322, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20713597 and 20713606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20713601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10356815 + 10356816.

It is an arithmetic number, because the mean of its divisors is an integer number (10356816).

Almost surely, 2^20713631 is an apocalyptic number.

20713631 is a deficient number, since it is larger than the sum of its proper divisors (1).

20713631 is an equidigital number, since it uses as much as digits as its factorization.

20713631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 23.

The square root of 20713631 is about 4551.2230224413. The cubic root of 20713631 is about 274.6325936528.

The spelling of 20713631 in words is "twenty million, seven hundred thirteen thousand, six hundred thirty-one".