64625665 has 8 divisors (see below), whose sum is σ = 83516328. Its totient is φ = 47723520.

The previous prime is 64625663. The next prime is 64625677. The reversal of 64625665 is 56652646.

It can be written as a sum of positive squares in 4 ways, for example, as 144 + 64625521 = 12^2 + 8039^2 .

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

It is not a de Polignac number, because 64625665 - 2¹ = 64625663 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64625663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 497056 + ... + 497185.

It is an arithmetic number, because the mean of its divisors is an integer number (10439541).

Almost surely, 2^64625665 is an apocalyptic number.

64625665 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

64625665 is a deficient number, since it is larger than the sum of its proper divisors (18890663).

64625665 is a wasteful number, since it uses less digits than its factorization.

64625665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 994259.

The product of its digits is 259200, while the sum is 40.

The square root of 64625665 is about 8039.0089563329. The cubic root of 64625665 is about 401.2992440929.

The spelling of 64625665 in words is "sixty-four million, six hundred twenty-five thousand, six hundred sixty-five".