64839217 has 2 divisors, whose sum is σ = 64839218. Its totient is φ = 64839216.

The previous prime is 64839199. The next prime is 64839263. The reversal of 64839217 is 71293846.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44036496 + 20802721 = 6636^2 + 4561^2 .

It is a cyclic number.

It is not a de Polignac number, because 64839217 - 2¹¹ = 64837169 is a prime.

It is a super-2 number, since 2×64839217² = 8408248122346178, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 64839217.

It is not a weakly prime, because it can be changed into another prime (64839017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32419608 + 32419609.

It is an arithmetic number, because the mean of its divisors is an integer number (32419609).

Almost surely, 2^64839217 is an apocalyptic number.

It is an amenable number.

64839217 is a deficient number, since it is larger than the sum of its proper divisors (1).

64839217 is an equidigital number, since it uses as much as digits as its factorization.

64839217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 72576, while the sum is 40.

The square root of 64839217 is about 8052.2802360574. The cubic root of 64839217 is about 401.7407819556.

It can be divided in two parts, 64839 and 217, that added together give a palindrome (65056).

The spelling of 64839217 in words is "sixty-four million, eight hundred thirty-nine thousand, two hundred seventeen".