646376665 has 16 divisors (see below), whose sum is σ = 864172800. Its totient is φ = 460088320.

The previous prime is 646376623. The next prime is 646376677. The reversal of 646376665 is 566673646.

It is not a de Polignac number, because 646376665 - 2¹³ = 646368473 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 122440 + ... + 127609.

It is an arithmetic number, because the mean of its divisors is an integer number (54010800).

Almost surely, 2^646376665 is an apocalyptic number.

It is an amenable number.

646376665 is a deficient number, since it is larger than the sum of its proper divisors (217796135).

646376665 is a wasteful number, since it uses less digits than its factorization.

646376665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250112.

The product of its digits is 3265920, while the sum is 49.

The square root of 646376665 is about 25423.9388175790. The cubic root of 646376665 is about 864.6265286062.

The spelling of 646376665 in words is "six hundred forty-six million, three hundred seventy-six thousand, six hundred sixty-five".