20198911 has 2 divisors, whose sum is σ = 20198912. Its totient is φ = 20198910.

The previous prime is 20198903. The next prime is 20198917. The reversal of 20198911 is 11989102.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20198911 - 2³ = 20198903 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20198917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10099455 + 10099456.

It is an arithmetic number, because the mean of its divisors is an integer number (10099456).

Almost surely, 2^20198911 is an apocalyptic number.

20198911 is a deficient number, since it is larger than the sum of its proper divisors (1).

20198911 is an equidigital number, since it uses as much as digits as its factorization.

20198911 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 20198911 is about 4494.3198595561. The cubic root of 20198911 is about 272.3386739741.

The spelling of 20198911 in words is "twenty million, one hundred ninety-eight thousand, nine hundred eleven".