64640319 has 8 divisors (see below), whose sum is σ = 86264112. Its totient is φ = 43055040.

The previous prime is 64640311. The next prime is 64640339. The reversal of 64640319 is 91304646.

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

It is not a de Polignac number, because 64640319 - 2³ = 64640311 is a prime.

It is a super-2 number, since 2×64640319² = 8356741680843522, which contains 22 as substring.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 64640319.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64640311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5452 + ... + 12609.

It is an arithmetic number, because the mean of its divisors is an integer number (10783014).

Almost surely, 2^64640319 is an apocalyptic number.

64640319 is a deficient number, since it is larger than the sum of its proper divisors (21623793).

64640319 is a wasteful number, since it uses less digits than its factorization.

64640319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19257.

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 64640319 is about 8039.9203354262. The cubic root of 64640319 is about 401.3295736051.

The spelling of 64640319 in words is "sixty-four million, six hundred forty thousand, three hundred nineteen".