664646515 has 8 divisors (see below), whose sum is σ = 858927888. Its totient is φ = 490815840.

The previous prime is 664646459. The next prime is 664646519. The reversal of 664646515 is 515646466.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 664646515 - 2¹⁹ = 664122227 is a prime.

It is not an unprimeable number, because it can be changed into a prime (664646519) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 5112601 + ... + 5112730.

It is an arithmetic number, because the mean of its divisors is an integer number (107365986).

Almost surely, 2^664646515 is an apocalyptic number.

664646515 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

664646515 is a deficient number, since it is larger than the sum of its proper divisors (194281373).

664646515 is a wasteful number, since it uses less digits than its factorization.

664646515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10225349.

The product of its digits is 518400, while the sum is 43.

The square root of 664646515 is about 25780.7392252433. The cubic root of 664646515 is about 872.6971894437.

The spelling of 664646515 in words is "six hundred sixty-four million, six hundred forty-six thousand, five hundred fifteen".