1686808631 has 2 divisors, whose sum is σ = 1686808632. Its totient is φ = 1686808630.

The previous prime is 1686808609. The next prime is 1686808633. The reversal of 1686808631 is 1368086861.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1686808631 - 2³⁰ = 613066807 is a prime.

It is a super-2 number, since 2×1686808631² = 5690646715232188322, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 1686808633, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1686808633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 843404315 + 843404316.

It is an arithmetic number, because the mean of its divisors is an integer number (843404316).

Almost surely, 2^1686808631 is an apocalyptic number.

1686808631 is a deficient number, since it is larger than the sum of its proper divisors (1).

1686808631 is an equidigital number, since it uses as much as digits as its factorization.

1686808631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 331776, while the sum is 47.

The square root of 1686808631 is about 41070.7758753107. The cubic root of 1686808631 is about 1190.3881771552.

The spelling of 1686808631 in words is "one billion, six hundred eighty-six million, eight hundred eight thousand, six hundred thirty-one".