664455756653666 has 8 divisors (see below), whose sum is σ = 1019862324166224. Its totient is φ = 324501648598260.

The previous prime is 664455756653653. The next prime is 664455756653671. The reversal of 664455756653666 is 666356657554466.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3863114864180 + ... + 3863114864351.

It is an arithmetic number, because the mean of its divisors is an integer number (127482790520778).

Almost surely, 2^{664455756653666} is an apocalyptic number.

664455756653666 is a deficient number, since it is larger than the sum of its proper divisors (355406567512558).

664455756653666 is a wasteful number, since it uses less digits than its factorization.

664455756653666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7726229728576.

The product of its digits is 58786560000, while the sum is 80.

The spelling of 664455756653666 in words is "six hundred sixty-four trillion, four hundred fifty-five billion, seven hundred fifty-six million, six hundred fifty-three thousand, six hundred sixty-six".