18896989 has 2 divisors, whose sum is σ = 18896990. Its totient is φ = 18896988.

The previous prime is 18896959. The next prime is 18896993. The reversal of 18896989 is 98969881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17724100 + 1172889 = 4210^2 + 1083^2 .

It is a cyclic number.

It is not a de Polignac number, because 18896989 - 2⁹ = 18896477 is a prime.

It is a super-2 number, since 2×18896989² = 714192386532242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18896939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9448494 + 9448495.

It is an arithmetic number, because the mean of its divisors is an integer number (9448495).

Almost surely, 2^18896989 is an apocalyptic number.

It is an amenable number.

18896989 is a deficient number, since it is larger than the sum of its proper divisors (1).

18896989 is an equidigital number, since it uses as much as digits as its factorization.

18896989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2239488, while the sum is 58.

The square root of 18896989 is about 4347.0667121635. The cubic root of 18896989 is about 266.3570543803.

The spelling of 18896989 in words is "eighteen million, eight hundred ninety-six thousand, nine hundred eighty-nine".