64972709 has 4 divisors (see below), whose sum is σ = 65603616. Its totient is φ = 64341804.

The previous prime is 64972679. The next prime is 64972711. The reversal of 64972709 is 90727946.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64972709 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 64972709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64972729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 315299 + ... + 315504.

It is an arithmetic number, because the mean of its divisors is an integer number (16400904).

Almost surely, 2^64972709 is an apocalyptic number.

It is an amenable number.

64972709 is a deficient number, since it is larger than the sum of its proper divisors (630907).

64972709 is a wasteful number, since it uses less digits than its factorization.

64972709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630906.

The product of its (nonzero) digits is 190512, while the sum is 44.

The square root of 64972709 is about 8060.5650546348. The cubic root of 64972709 is about 402.0162963782.

The spelling of 64972709 in words is "sixty-four million, nine hundred seventy-two thousand, seven hundred nine".