64513985 has 16 divisors (see below), whose sum is σ = 79497936. Its totient is φ = 50239488.

The previous prime is 64513979. The next prime is 64514029. The reversal of 64513985 is 58931546.

It can be written as a sum of positive squares in 8 ways, for example, as 529984 + 63984001 = 728^2 + 7999^2 .

It is a cyclic number.

It is not a de Polignac number, because 64513985 - 2⁶ = 64513921 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35417 + ... + 37193.

It is an arithmetic number, because the mean of its divisors is an integer number (4968621).

Almost surely, 2^64513985 is an apocalyptic number.

It is an amenable number.

64513985 is a deficient number, since it is larger than the sum of its proper divisors (14983951).

64513985 is a wasteful number, since it uses less digits than its factorization.

64513985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1972.

The product of its digits is 129600, while the sum is 41.

The square root of 64513985 is about 8032.0598229844. The cubic root of 64513985 is about 401.0679482621.

The spelling of 64513985 in words is "sixty-four million, five hundred thirteen thousand, nine hundred eighty-five".