64685893 has 4 divisors (see below), whose sum is σ = 64703980. Its totient is φ = 64667808.

The previous prime is 64685857. The next prime is 64685909. The reversal of 64685893 is 39858646.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 56580484 + 8105409 = 7522^2 + 2847^2 .

It is a cyclic number.

It is not a de Polignac number, because 64685893 - 2¹⁷ = 64554821 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64685293) 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, 1680 + ... + 11497.

It is an arithmetic number, because the mean of its divisors is an integer number (16175995).

Almost surely, 2^64685893 is an apocalyptic number.

It is an amenable number.

64685893 is a deficient number, since it is larger than the sum of its proper divisors (18087).

64685893 is a wasteful number, since it uses less digits than its factorization.

64685893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18086.

The product of its digits is 1244160, while the sum is 49.

The square root of 64685893 is about 8042.7540681038. The cubic root of 64685893 is about 401.4238692270.

The spelling of 64685893 in words is "sixty-four million, six hundred eighty-five thousand, eight hundred ninety-three".