64636247813 has 2 divisors, whose sum is σ = 64636247814. Its totient is φ = 64636247812.

The previous prime is 64636247807. The next prime is 64636247821. The reversal of 64636247813 is 31874263646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 52707894724 + 11928353089 = 229582^2 + 109217^2 .

It is a cyclic number.

It is not a de Polignac number, because 64636247813 - 2¹² = 64636243717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64636247833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32318123906 + 32318123907.

It is an arithmetic number, because the mean of its divisors is an integer number (32318123907).

Almost surely, 2^64636247813 is an apocalyptic number.

It is an amenable number.

64636247813 is a deficient number, since it is larger than the sum of its proper divisors (1).

64636247813 is an equidigital number, since it uses as much as digits as its factorization.

64636247813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3483648, while the sum is 50.

The spelling of 64636247813 in words is "sixty-four billion, six hundred thirty-six million, two hundred forty-seven thousand, eight hundred thirteen".