664989465 has 16 divisors (see below), whose sum is σ = 1215980928. Its totient is φ = 303995136.

The previous prime is 664989433. The next prime is 664989467. The reversal of 664989465 is 564989466.

It is a happy number.

It is not a de Polignac number, because 664989465 - 2⁵ = 664989433 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664989467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3166512 + ... + 3166721.

It is an arithmetic number, because the mean of its divisors is an integer number (75998808).

Almost surely, 2^664989465 is an apocalyptic number.

It is an amenable number.

664989465 is a deficient number, since it is larger than the sum of its proper divisors (550991463).

664989465 is a wasteful number, since it uses less digits than its factorization.

664989465 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6333248.

The product of its digits is 11197440, while the sum is 57.

The square root of 664989465 is about 25787.3896507576. The cubic root of 664989465 is about 872.8472642238.

Subtracting from 664989465 its reverse (564989466), we obtain a palindrome (99999999).

The spelling of 664989465 in words is "six hundred sixty-four million, nine hundred eighty-nine thousand, four hundred sixty-five".