19980458917 has 2 divisors, whose sum is σ = 19980458918. Its totient is φ = 19980458916.

The previous prime is 19980458867. The next prime is 19980458959. The reversal of 19980458917 is 71985408991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18114737281 + 1865721636 = 134591^2 + 43194^2 .

It is a cyclic number.

It is not a de Polignac number, because 19980458917 - 2¹⁵ = 19980426149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19980458977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9990229458 + 9990229459.

It is an arithmetic number, because the mean of its divisors is an integer number (9990229459).

Almost surely, 2^19980458917 is an apocalyptic number.

It is an amenable number.

19980458917 is a deficient number, since it is larger than the sum of its proper divisors (1).

19980458917 is an equidigital number, since it uses as much as digits as its factorization.

19980458917 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6531840, while the sum is 61.

The spelling of 19980458917 in words is "nineteen billion, nine hundred eighty million, four hundred fifty-eight thousand, nine hundred seventeen".