64739989 has 2 divisors, whose sum is σ = 64739990. Its totient is φ = 64739988.

The previous prime is 64739953. The next prime is 64739999. The reversal of 64739989 is 98993746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 40068900 + 24671089 = 6330^2 + 4967^2 .

It is a cyclic number.

It is not a de Polignac number, because 64739989 - 2¹⁵ = 64707221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64739999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32369994 + 32369995.

It is an arithmetic number, because the mean of its divisors is an integer number (32369995).

Almost surely, 2^64739989 is an apocalyptic number.

It is an amenable number.

64739989 is a deficient number, since it is larger than the sum of its proper divisors (1).

64739989 is an equidigital number, since it uses as much as digits as its factorization.

64739989 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2939328, while the sum is 55.

The square root of 64739989 is about 8046.1163923970. The cubic root of 64739989 is about 401.5357399610.

The spelling of 64739989 in words is "sixty-four million, seven hundred thirty-nine thousand, nine hundred eighty-nine".