64646555564729 has 2 divisors, whose sum is σ = 64646555564730. Its totient is φ = 64646555564728.

The previous prime is 64646555564609. The next prime is 64646555564809. The reversal of 64646555564729 is 92746555564646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47321356418704 + 17325199146025 = 6879052^2 + 4162355^2 .

It is a cyclic number.

It is not a de Polignac number, because 64646555564729 - 2³⁶ = 64577836087993 is a prime.

It is a super-2 number, since 2×64646555564729² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (64646555564329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32323277782364 + 32323277782365.

It is an arithmetic number, because the mean of its divisors is an integer number (32323277782365).

Almost surely, 2^{64646555564729} is an apocalyptic number.

It is an amenable number.

64646555564729 is a deficient number, since it is larger than the sum of its proper divisors (1).

64646555564729 is an equidigital number, since it uses as much as digits as its factorization.

64646555564729 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6531840000, while the sum is 74.

The spelling of 64646555564729 in words is "sixty-four trillion, six hundred forty-six billion, five hundred fifty-five million, five hundred sixty-four thousand, seven hundred twenty-nine".