64729439 has 2 divisors, whose sum is σ = 64729440. Its totient is φ = 64729438.

The previous prime is 64729411. The next prime is 64729463. The reversal of 64729439 is 93492746.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64729439 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 64729439.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64729139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32364719 + 32364720.

It is an arithmetic number, because the mean of its divisors is an integer number (32364720).

Almost surely, 2^64729439 is an apocalyptic number.

64729439 is a deficient number, since it is larger than the sum of its proper divisors (1).

64729439 is an equidigital number, since it uses as much as digits as its factorization.

64729439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 44.

The square root of 64729439 is about 8045.4607699000. The cubic root of 64729439 is about 401.5139274139.

The spelling of 64729439 in words is "sixty-four million, seven hundred twenty-nine thousand, four hundred thirty-nine".