664637654 has 8 divisors (see below), whose sum is σ = 997102440. Its totient is φ = 332270176.

The previous prime is 664637653. The next prime is 664637657. The reversal of 664637654 is 456736466.

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

It is a super-2 number, since 2×664637654² = 883486422229247432, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 664637599 and 664637608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664637653) 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, 3779 + ... + 36654.

It is an arithmetic number, because the mean of its divisors is an integer number (124637805).

Almost surely, 2^664637654 is an apocalyptic number.

664637654 is a deficient number, since it is larger than the sum of its proper divisors (332464786).

664637654 is a wasteful number, since it uses less digits than its factorization.

664637654 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48654.

The product of its digits is 2177280, while the sum is 47.

The square root of 664637654 is about 25780.5673715688. The cubic root of 664637654 is about 872.6933111896.

The spelling of 664637654 in words is "six hundred sixty-four million, six hundred thirty-seven thousand, six hundred fifty-four".