664677409 has 8 divisors (see below), whose sum is σ = 728785728. Its totient is φ = 601182960.

The previous prime is 664677401. The next prime is 664677427. The reversal of 664677409 is 904776466.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 664677409 - 2³ = 664677401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664677401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151197 + ... + 155530.

It is an arithmetic number, because the mean of its divisors is an integer number (91098216).

Almost surely, 2^664677409 is an apocalyptic number.

It is an amenable number.

664677409 is a deficient number, since it is larger than the sum of its proper divisors (64108319).

664677409 is a wasteful number, since it uses less digits than its factorization.

664677409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306935.

The product of its (nonzero) digits is 1524096, while the sum is 49.

The square root of 664677409 is about 25781.3383865152. The cubic root of 664677409 is about 872.7107107610.

The spelling of 664677409 in words is "six hundred sixty-four million, six hundred seventy-seven thousand, four hundred nine".