198696989 has 2 divisors, whose sum is σ = 198696990. Its totient is φ = 198696988.

The previous prime is 198696943. The next prime is 198697027. The reversal of 198696989 is 989696891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 122832889 + 75864100 = 11083^2 + 8710^2 .

It is a cyclic number.

It is not a de Polignac number, because 198696989 - 2⁸ = 198696733 is a prime.

It is a super-2 number, since 2×198696989² = 78960986875332242, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198696389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99348494 + 99348495.

It is an arithmetic number, because the mean of its divisors is an integer number (99348495).

Almost surely, 2^198696989 is an apocalyptic number.

It is an amenable number.

198696989 is a deficient number, since it is larger than the sum of its proper divisors (1).

198696989 is an equidigital number, since it uses as much as digits as its factorization.

198696989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15116544, while the sum is 65.

The square root of 198696989 is about 14095.9919480681. The cubic root of 198696989 is about 583.5307704642.

The spelling of 198696989 in words is "one hundred ninety-eight million, six hundred ninety-six thousand, nine hundred eighty-nine".