667949687 has 2 divisors, whose sum is σ = 667949688. Its totient is φ = 667949686.

The previous prime is 667949683. The next prime is 667949773. The reversal of 667949687 is 786949766.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 667949687 - 2² = 667949683 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (667949683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333974843 + 333974844.

It is an arithmetic number, because the mean of its divisors is an integer number (333974844).

Almost surely, 2^667949687 is an apocalyptic number.

667949687 is a deficient number, since it is larger than the sum of its proper divisors (1).

667949687 is an equidigital number, since it uses as much as digits as its factorization.

667949687 is an evil number, because the sum of its binary digits is even.

The product of its digits is 27433728, while the sum is 62.

The square root of 667949687 is about 25844.7226141044. The cubic root of 667949687 is about 874.1405163605.

The spelling of 667949687 in words is "six hundred sixty-seven million, nine hundred forty-nine thousand, six hundred eighty-seven".