64439213 has 4 divisors (see below), whose sum is σ = 64811868. Its totient is φ = 64066560.

The previous prime is 64439191. The next prime is 64439227. The reversal of 64439213 is 31293446.

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 61418569 + 3020644 = 7837^2 + 1738^2 .

It is a cyclic number.

It is not a de Polignac number, because 64439213 - 2¹⁰ = 64438189 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 64439213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64439233) 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, 186068 + ... + 186413.

It is an arithmetic number, because the mean of its divisors is an integer number (16202967).

Almost surely, 2^64439213 is an apocalyptic number.

It is an amenable number.

64439213 is a deficient number, since it is larger than the sum of its proper divisors (372655).

64439213 is a wasteful number, since it uses less digits than its factorization.

64439213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 372654.

The product of its digits is 15552, while the sum is 32.

The square root of 64439213 is about 8027.4038767213. The cubic root of 64439213 is about 400.9129418411.

The spelling of 64439213 in words is "sixty-four million, four hundred thirty-nine thousand, two hundred thirteen".