19983943493 has 2 divisors, whose sum is σ = 19983943494. Its totient is φ = 19983943492.

The previous prime is 19983943487. The next prime is 19983943531. The reversal of 19983943493 is 39434938991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19516648804 + 467294689 = 139702^2 + 21617^2 .

It is a cyclic number.

It is not a de Polignac number, because 19983943493 - 2⁶ = 19983943429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19983943393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9991971746 + 9991971747.

It is an arithmetic number, because the mean of its divisors is an integer number (9991971747).

Almost surely, 2^19983943493 is an apocalyptic number.

It is an amenable number.

19983943493 is a deficient number, since it is larger than the sum of its proper divisors (1).

19983943493 is an equidigital number, since it uses as much as digits as its factorization.

19983943493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22674816, while the sum is 62.

The spelling of 19983943493 in words is "nineteen billion, nine hundred eighty-three million, nine hundred forty-three thousand, four hundred ninety-three".