64631665 has 8 divisors (see below), whose sum is σ = 88637760. Its totient is φ = 44318832.

The previous prime is 64631657. The next prime is 64631669. The reversal of 64631665 is 56613646.

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

It is a cyclic number.

It is not a de Polignac number, because 64631665 - 2³ = 64631657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (64631669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 923275 + ... + 923344.

It is an arithmetic number, because the mean of its divisors is an integer number (11079720).

Almost surely, 2^64631665 is an apocalyptic number.

It is an amenable number.

64631665 is a deficient number, since it is larger than the sum of its proper divisors (24006095).

64631665 is a wasteful number, since it uses less digits than its factorization.

64631665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1846631.

The product of its digits is 77760, while the sum is 37.

The square root of 64631665 is about 8039.3821279996. The cubic root of 64631665 is about 401.3116628997.

It can be divided in two parts, 6463 and 1665, that added together give a triangular number (8128 = T₁₂₇).

The spelling of 64631665 in words is "sixty-four million, six hundred thirty-one thousand, six hundred sixty-five".