64940013 has 6 divisors (see below), whose sum is σ = 93802254. Its totient is φ = 43293336.

The previous prime is 64939993. The next prime is 64940021. The reversal of 64940013 is 31004946.

64940013 is a `hidden beast` number, since 649 + 4 + 0 + 0 + 13 = 666.

It can be written as a sum of positive squares in only one way, i.e., 64931364 + 8649 = 8058^2 + 93^2 .

It is not a de Polignac number, because 64940013 - 2⁵ = 64939981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64940033) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3607770 + ... + 3607787.

It is an arithmetic number, because the mean of its divisors is an integer number (15633709).

Almost surely, 2^64940013 is an apocalyptic number.

It is an amenable number.

64940013 is a deficient number, since it is larger than the sum of its proper divisors (28862241).

64940013 is a wasteful number, since it uses less digits than its factorization.

64940013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7215563 (or 7215560 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 64940013 is about 8058.5366537604. The cubic root of 64940013 is about 401.9488499559.

Adding to 64940013 its reverse (31004946), we get a palindrome (95944959).

The spelling of 64940013 in words is "sixty-four million, nine hundred forty thousand, thirteen".