19894980493 has 2 divisors, whose sum is σ = 19894980494. Its totient is φ = 19894980492.

The previous prime is 19894980463. The next prime is 19894980499. The reversal of 19894980493 is 39408949891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17105239369 + 2789741124 = 130787^2 + 52818^2 .

It is a cyclic number.

It is not a de Polignac number, because 19894980493 - 2⁹ = 19894979981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19894980499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9947490246 + 9947490247.

It is an arithmetic number, because the mean of its divisors is an integer number (9947490247).

Almost surely, 2^19894980493 is an apocalyptic number.

It is an amenable number.

19894980493 is a deficient number, since it is larger than the sum of its proper divisors (1).

19894980493 is an equidigital number, since it uses as much as digits as its factorization.

19894980493 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20155392, while the sum is 64.

The spelling of 19894980493 in words is "nineteen billion, eight hundred ninety-four million, nine hundred eighty thousand, four hundred ninety-three".