64399297 has 4 divisors (see below), whose sum is σ = 64666756. Its totient is φ = 64131840.

The previous prime is 64399273. The next prime is 64399319. The reversal of 64399297 is 79299346.

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 58003456 + 6395841 = 7616^2 + 2529^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64399297 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 64399297.

It is not an unprimeable number, because it can be changed into a prime (64399597) 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, 133368 + ... + 133849.

It is an arithmetic number, because the mean of its divisors is an integer number (16166689).

Almost surely, 2^64399297 is an apocalyptic number.

It is an amenable number.

64399297 is a deficient number, since it is larger than the sum of its proper divisors (267459).

64399297 is a wasteful number, since it uses less digits than its factorization.

64399297 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267458.

The product of its digits is 734832, while the sum is 49.

The square root of 64399297 is about 8024.9172581404. The cubic root of 64399297 is about 400.8301447076.

Adding to 64399297 its sum of digits (49), we get a palindrome (64399346).

The spelling of 64399297 in words is "sixty-four million, three hundred ninety-nine thousand, two hundred ninety-seven".