19926368857 has 2 divisors, whose sum is σ = 19926368858. Its totient is φ = 19926368856.

The previous prime is 19926368783. The next prime is 19926368863. The reversal of 19926368857 is 75886362991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10219390281 + 9706978576 = 101091^2 + 98524^2 .

It is a cyclic number.

It is not a de Polignac number, because 19926368857 - 2²⁷ = 19792151129 is a prime.

It is not a weakly prime, because it can be changed into another prime (19926366857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9963184428 + 9963184429.

It is an arithmetic number, because the mean of its divisors is an integer number (9963184429).

Almost surely, 2^19926368857 is an apocalyptic number.

It is an amenable number.

19926368857 is a deficient number, since it is larger than the sum of its proper divisors (1).

19926368857 is an equidigital number, since it uses as much as digits as its factorization.

19926368857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 39191040, while the sum is 64.

The spelling of 19926368857 in words is "nineteen billion, nine hundred twenty-six million, three hundred sixty-eight thousand, eight hundred fifty-seven".