64400666 has 8 divisors (see below), whose sum is σ = 105382944. Its totient is φ = 29273020.

The previous prime is 64400663. The next prime is 64400717. The reversal of 64400666 is 66600446.

It is a happy number.

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

It is not an unprimeable number, because it can be changed into a prime (64400663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1463630 + ... + 1463673.

It is an arithmetic number, because the mean of its divisors is an integer number (13172868).

Almost surely, 2^64400666 is an apocalyptic number.

64400666 is a deficient number, since it is larger than the sum of its proper divisors (40982278).

64400666 is a wasteful number, since it uses less digits than its factorization.

64400666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2927316.

The product of its (nonzero) digits is 20736, while the sum is 32.

The square root of 64400666 is about 8025.0025545167. The cubic root of 64400666 is about 400.8329849693.

The spelling of 64400666 in words is "sixty-four million, four hundred thousand, six hundred sixty-six".