18896921 has 2 divisors, whose sum is σ = 18896922. Its totient is φ = 18896920.

The previous prime is 18896897. The next prime is 18896939. The reversal of 18896921 is 12969881.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14714896 + 4182025 = 3836^2 + 2045^2 .

It is a cyclic number.

It is not a de Polignac number, because 18896921 - 2¹⁰ = 18895897 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18896321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9448460 + 9448461.

It is an arithmetic number, because the mean of its divisors is an integer number (9448461).

Almost surely, 2^18896921 is an apocalyptic number.

It is an amenable number.

18896921 is a deficient number, since it is larger than the sum of its proper divisors (1).

18896921 is an equidigital number, since it uses as much as digits as its factorization.

18896921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62208, while the sum is 44.

The square root of 18896921 is about 4347.0588907904. The cubic root of 18896921 is about 266.3567348884.

The spelling of 18896921 in words is "eighteen million, eight hundred ninety-six thousand, nine hundred twenty-one".