664021413 has 24 divisors (see below), whose sum is σ = 1052781600. Its totient is φ = 399958560.

The previous prime is 664021403. The next prime is 664021429. The reversal of 664021413 is 314120466.

664021413 is a `hidden beast` number, since 6 + 640 + 2 + 1 + 4 + 13 = 666.

It is not a de Polignac number, because 664021413 - 2⁸ = 664021157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (664021403) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4438 + ... + 36711.

It is an arithmetic number, because the mean of its divisors is an integer number (43865900).

Almost surely, 2^664021413 is an apocalyptic number.

It is an amenable number.

664021413 is a deficient number, since it is larger than the sum of its proper divisors (388760187).

664021413 is a wasteful number, since it uses less digits than its factorization.

664021413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41329 (or 41326 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 664021413 is about 25768.6129428807. The cubic root of 664021413 is about 872.4235122041.

Adding to 664021413 its reverse (314120466), we get a palindrome (978141879).

The spelling of 664021413 in words is "six hundred sixty-four million, twenty-one thousand, four hundred thirteen".