673787665 has 8 divisors (see below), whose sum is σ = 816551208. Its totient is φ = 533692800.

The previous prime is 673787641. The next prime is 673787677. The reversal of 673787665 is 566787376.

It can be written as a sum of positive squares in 4 ways, for example, as 203461696 + 470325969 = 14264^2 + 21687^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 673787665 - 2²⁵ = 640233233 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 666612 + ... + 667621.

It is an arithmetic number, because the mean of its divisors is an integer number (102068901).

Almost surely, 2^673787665 is an apocalyptic number.

It is an amenable number.

673787665 is a deficient number, since it is larger than the sum of its proper divisors (142763543).

673787665 is a wasteful number, since it uses less digits than its factorization.

673787665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1334339.

The product of its digits is 8890560, while the sum is 55.

The square root of 673787665 is about 25957.4202300614. The cubic root of 673787665 is about 876.6798379923.

The spelling of 673787665 in words is "six hundred seventy-three million, seven hundred eighty-seven thousand, six hundred sixty-five".