664381306 has 4 divisors (see below), whose sum is σ = 996571962. Its totient is φ = 332190652.

The previous prime is 664381279. The next prime is 664381307. The reversal of 664381306 is 603183466.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 662599081 + 1782225 = 25741^2 + 1335^2 .

It is not an unprimeable number, because it can be changed into a prime (664381307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166095325 + ... + 166095328.

Almost surely, 2^664381306 is an apocalyptic number.

664381306 is a deficient number, since it is larger than the sum of its proper divisors (332190656).

664381306 is a wasteful number, since it uses less digits than its factorization.

664381306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 332190655.

The product of its (nonzero) digits is 62208, while the sum is 37.

The square root of 664381306 is about 25775.5951628668. The cubic root of 664381306 is about 872.5810986923.

The spelling of 664381306 in words is "six hundred sixty-four million, three hundred eighty-one thousand, three hundred six".