17517791989 has 2 divisors, whose sum is σ = 17517791990. Its totient is φ = 17517791988.

The previous prime is 17517791971. The next prime is 17517792041. The reversal of 17517791989 is 98919771571.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14168855089 + 3348936900 = 119033^2 + 57870^2 .

It is a cyclic number.

It is not a de Polignac number, because 17517791989 - 2¹³ = 17517783797 is a prime.

It is a super-2 number, since 2×17517791989² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 17517791989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17517791909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8758895994 + 8758895995.

It is an arithmetic number, because the mean of its divisors is an integer number (8758895995).

Almost surely, 2^17517791989 is an apocalyptic number.

It is an amenable number.

17517791989 is a deficient number, since it is larger than the sum of its proper divisors (1).

17517791989 is an equidigital number, since it uses as much as digits as its factorization.

17517791989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10001880, while the sum is 64.

The spelling of 17517791989 in words is "seventeen billion, five hundred seventeen million, seven hundred ninety-one thousand, nine hundred eighty-nine".