665456644 has 12 divisors (see below), whose sum is σ = 1189327104. Its totient is φ = 325648904.

The previous prime is 665456641. The next prime is 665456657. The reversal of 665456644 is 446654566.

It is a junction number, because it is equal to n+sod(n) for n = 665456594 and 665456603.

It is not an unprimeable number, because it can be changed into a prime (665456641) 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, 1769644 + ... + 1770019.

It is an arithmetic number, because the mean of its divisors is an integer number (99110592).

Almost surely, 2^665456644 is an apocalyptic number.

It is an amenable number.

665456644 is a deficient number, since it is larger than the sum of its proper divisors (523870460).

665456644 is a wasteful number, since it uses less digits than its factorization.

665456644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3539714 (or 3539712 counting only the distinct ones).

The product of its digits is 2073600, while the sum is 46.

The square root of 665456644 is about 25796.4463444095. The cubic root of 665456644 is about 873.0516185675.

The spelling of 665456644 in words is "six hundred sixty-five million, four hundred fifty-six thousand, six hundred forty-four".