19943003257 has 2 divisors, whose sum is σ = 19943003258. Its totient is φ = 19943003256.

The previous prime is 19943003251. The next prime is 19943003261. The reversal of 19943003257 is 75230034991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14622613776 + 5320389481 = 120924^2 + 72941^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19943003257 is a prime.

It is not a weakly prime, because it can be changed into another prime (19943003251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9971501628 + 9971501629.

It is an arithmetic number, because the mean of its divisors is an integer number (9971501629).

Almost surely, 2^19943003257 is an apocalyptic number.

It is an amenable number.

19943003257 is a deficient number, since it is larger than the sum of its proper divisors (1).

19943003257 is an equidigital number, since it uses as much as digits as its factorization.

19943003257 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 204120, while the sum is 43.

The spelling of 19943003257 in words is "nineteen billion, nine hundred forty-three million, three thousand, two hundred fifty-seven".