664412121 has 24 divisors (see below), whose sum is σ = 1011296000. Its totient is φ = 419180832.

The previous prime is 664412117. The next prime is 664412129. The reversal of 664412121 is 121214466.

664412121 is a `hidden beast` number, since 6 + 6 + 441 + 212 + 1 = 666.

It is not a de Polignac number, because 664412121 - 2² = 664412117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664412129) 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, 243000 + ... + 245718.

Almost surely, 2^664412121 is an apocalyptic number.

It is an amenable number.

664412121 is a deficient number, since it is larger than the sum of its proper divisors (346883879).

664412121 is a wasteful number, since it uses less digits than its factorization.

664412121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4173 (or 4170 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 664412121 is about 25776.1929112893. The cubic root of 664412121 is about 872.5945890232.

Adding to 664412121 its reverse (121214466), we get a palindrome (785626587).

The spelling of 664412121 in words is "six hundred sixty-four million, four hundred twelve thousand, one hundred twenty-one".