64691726213 has 2 divisors, whose sum is σ = 64691726214. Its totient is φ = 64691726212.

The previous prime is 64691726173. The next prime is 64691726279. The reversal of 64691726213 is 31262719646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64443884164 + 247842049 = 253858^2 + 15743^2 .

It is a cyclic number.

It is not a de Polignac number, because 64691726213 - 2²⁰ = 64690677637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64691726413) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32345863106 + 32345863107.

It is an arithmetic number, because the mean of its divisors is an integer number (32345863107).

Almost surely, 2^64691726213 is an apocalyptic number.

It is an amenable number.

64691726213 is a deficient number, since it is larger than the sum of its proper divisors (1).

64691726213 is an equidigital number, since it uses as much as digits as its factorization.

64691726213 is an evil number, because the sum of its binary digits is even.

The product of its digits is 653184, while the sum is 47.

The spelling of 64691726213 in words is "sixty-four billion, six hundred ninety-one million, seven hundred twenty-six thousand, two hundred thirteen".