64641136502513 has 4 divisors (see below), whose sum is σ = 64641179352948. Its totient is φ = 64641093652080.

The previous prime is 64641136502489. The next prime is 64641136502563. The reversal of 64641136502513 is 31520563114646.

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 51497444573584 + 13143691928929 = 7176172^2 + 3625423^2 .

It is a cyclic number.

It is not a de Polignac number, because 64641136502513 - 2¹⁰ = 64641136501489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64641136502563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19076606 + ... + 22208087.

It is an arithmetic number, because the mean of its divisors is an integer number (16160294838237).

Almost surely, 2^{64641136502513} is an apocalyptic number.

It is an amenable number.

64641136502513 is a deficient number, since it is larger than the sum of its proper divisors (42850435).

64641136502513 is a wasteful number, since it uses less digits than its factorization.

64641136502513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42850434.

The product of its (nonzero) digits is 1555200, while the sum is 47.

The spelling of 64641136502513 in words is "sixty-four trillion, six hundred forty-one billion, one hundred thirty-six million, five hundred two thousand, five hundred thirteen".