664377472 has 128 divisors (see below), whose sum is σ = 1526817600. Its totient is φ = 285143040.

The previous prime is 664377457. The next prime is 664377479. The reversal of 664377472 is 274773466.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×664377472² = 882794850602221568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (664377479) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2163943 + ... + 2164249.

Almost surely, 2^664377472 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664377472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (763408800).

664377472 is an abundant number, since it is smaller than the sum of its proper divisors (862440128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

664377472 is a wasteful number, since it uses less digits than its factorization.

664377472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414 (or 402 counting only the distinct ones).

The product of its digits is 1185408, while the sum is 46.

The square root of 664377472 is about 25775.5207900830. The cubic root of 664377472 is about 872.5794201972.

The spelling of 664377472 in words is "six hundred sixty-four million, three hundred seventy-seven thousand, four hundred seventy-two".