664415 has 8 divisors (see below), whose sum is σ = 807408. Its totient is φ = 524800.

The previous prime is 664403. The next prime is 664421. The reversal of 664415 is 514466.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-664415 is a prime.

It is a Duffinian number.

It is a plaindrome in base 9.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 386 + ... + 1215.

It is an arithmetic number, because the mean of its divisors is an integer number (100926).

2⁶⁶⁴⁴¹⁵ is an apocalyptic number.

664415 is a deficient number, since it is larger than the sum of its proper divisors (142993).

664415 is a wasteful number, since it uses less digits than its factorization.

664415 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1689.

The product of its digits is 2880, while the sum is 26.

The square root of 664415 is about 815.1165560826. The cubic root of 664415 is about 87.2595849384.

The spelling of 664415 in words is "six hundred sixty-four thousand, four hundred fifteen".