664617911 has 6 divisors (see below), whose sum is σ = 688326912. Its totient is φ = 641699240.

The previous prime is 664617901. The next prime is 664617917. The reversal of 664617911 is 119716466.

It is not a de Polignac number, because 664617911 - 2²² = 660423607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664617917) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 394295 + ... + 395976.

It is an arithmetic number, because the mean of its divisors is an integer number (114721152).

Almost surely, 2^664617911 is an apocalyptic number.

664617911 is a deficient number, since it is larger than the sum of its proper divisors (23709001).

664617911 is an equidigital number, since it uses as much as digits as its factorization.

664617911 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 790329 (or 790300 counting only the distinct ones).

The product of its digits is 54432, while the sum is 41.

The square root of 664617911 is about 25780.1844640414. The cubic root of 664617911 is about 872.6846700127.

The spelling of 664617911 in words is "six hundred sixty-four million, six hundred seventeen thousand, nine hundred eleven".