64644440626357 has 2 divisors, whose sum is σ = 64644440626358. Its totient is φ = 64644440626356.

The previous prime is 64644440626273. The next prime is 64644440626379. The reversal of 64644440626357 is 75362604444646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52985500624996 + 11658940001361 = 7279114^2 + 3414519^2 .

It is a cyclic number.

It is not a de Polignac number, because 64644440626357 - 2⁷ = 64644440626229 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 64644440626295 and 64644440626304.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64644440626457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32322220313178 + 32322220313179.

It is an arithmetic number, because the mean of its divisors is an integer number (32322220313179).

Almost surely, 2^{64644440626357} is an apocalyptic number.

It is an amenable number.

64644440626357 is a deficient number, since it is larger than the sum of its proper divisors (1).

64644440626357 is an equidigital number, since it uses as much as digits as its factorization.

64644440626357 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 278691840, while the sum is 61.

The spelling of 64644440626357 in words is "sixty-four trillion, six hundred forty-four billion, four hundred forty million, six hundred twenty-six thousand, three hundred fifty-seven".