6687631 has 2 divisors, whose sum is σ = 6687632. Its totient is φ = 6687630.

The previous prime is 6687623. The next prime is 6687689. The reversal of 6687631 is 1367866.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6687631 - 2³ = 6687623 is a prime.

It is a super-2 number, since 2×6687631² = 89448816784322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6687931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3343815 + 3343816.

It is an arithmetic number, because the mean of its divisors is an integer number (3343816).

Almost surely, 2^6687631 is an apocalyptic number.

6687631 is a deficient number, since it is larger than the sum of its proper divisors (1).

6687631 is an equidigital number, since it uses as much as digits as its factorization.

6687631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 37.

The square root of 6687631 is about 2586.0454365691. The cubic root of 6687631 is about 188.4042812724.

The spelling of 6687631 in words is "six million, six hundred eighty-seven thousand, six hundred thirty-one".