669736987 has 2 divisors, whose sum is σ = 669736988. Its totient is φ = 669736986.

The previous prime is 669736979. The next prime is 669737011. The reversal of 669736987 is 789637966.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 669736987 - 2³ = 669736979 is a prime.

It is not a weakly prime, because it can be changed into another prime (669736937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334868493 + 334868494.

It is an arithmetic number, because the mean of its divisors is an integer number (334868494).

Almost surely, 2^669736987 is an apocalyptic number.

669736987 is a deficient number, since it is larger than the sum of its proper divisors (1).

669736987 is an equidigital number, since it uses as much as digits as its factorization.

669736987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20575296, while the sum is 61.

The square root of 669736987 is about 25879.2771730588. The cubic root of 669736987 is about 874.9194971379.

The spelling of 669736987 in words is "six hundred sixty-nine million, seven hundred thirty-six thousand, nine hundred eighty-seven".