64728319 has 8 divisors (see below), whose sum is σ = 67050000. Its totient is φ = 62412672.

The previous prime is 64728311. The next prime is 64728331. The reversal of 64728319 is 91382746.

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

It is a cyclic number.

It is not a de Polignac number, because 64728319 - 2³ = 64728311 is a prime.

It is a super-2 number, since 2×64728319² = 8379510561131522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64728311) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42432 + ... + 43930.

It is an arithmetic number, because the mean of its divisors is an integer number (8381250).

Almost surely, 2^64728319 is an apocalyptic number.

64728319 is a deficient number, since it is larger than the sum of its proper divisors (2321681).

64728319 is a wasteful number, since it uses less digits than its factorization.

64728319 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3017.

The product of its digits is 72576, while the sum is 40.

The square root of 64728319 is about 8045.3911651330. The cubic root of 64728319 is about 401.5116116299.

The spelling of 64728319 in words is "sixty-four million, seven hundred twenty-eight thousand, three hundred nineteen".