664212415 has 4 divisors (see below), whose sum is σ = 797054904. Its totient is φ = 531369928.

The previous prime is 664212407. The next prime is 664212427. The reversal of 664212415 is 514212466.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 664212415 - 2³ = 664212407 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66421237 + ... + 66421246.

It is an arithmetic number, because the mean of its divisors is an integer number (199263726).

Almost surely, 2^664212415 is an apocalyptic number.

664212415 is a deficient number, since it is larger than the sum of its proper divisors (132842489).

664212415 is a wasteful number, since it uses less digits than its factorization.

664212415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132842488.

The product of its digits is 11520, while the sum is 31.

The square root of 664212415 is about 25772.3187742198. The cubic root of 664212415 is about 872.5071534130.

The spelling of 664212415 in words is "six hundred sixty-four million, two hundred twelve thousand, four hundred fifteen".