64185813 has 12 divisors (see below), whose sum is σ = 92933568. Its totient is φ = 42688680.

The previous prime is 64185767. The next prime is 64185833. The reversal of 64185813 is 31858146.

64185813 is a `hidden beast` number, since 64 + 18 + 581 + 3 = 666.

It is not a de Polignac number, because 64185813 - 2⁹ = 64185301 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64185833) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4395 + ... + 12152.

It is an arithmetic number, because the mean of its divisors is an integer number (7744464).

Almost surely, 2^64185813 is an apocalyptic number.

It is an amenable number.

64185813 is a deficient number, since it is larger than the sum of its proper divisors (28747755).

64185813 is a wasteful number, since it uses less digits than its factorization.

64185813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16984 (or 16981 counting only the distinct ones).

The product of its digits is 23040, while the sum is 36.

The square root of 64185813 is about 8011.6048954002. The cubic root of 64185813 is about 400.3867363836.

The spelling of 64185813 in words is "sixty-four million, one hundred eighty-five thousand, eight hundred thirteen".