18911457 has 12 divisors (see below), whose sum is σ = 28198144. Its totient is φ = 12200760.

The previous prime is 18911413. The next prime is 18911461. The reversal of 18911457 is 75411981.

It is not a de Polignac number, because 18911457 - 2¹⁶ = 18845921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18911657) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33613 + ... + 34170.

Almost surely, 2^18911457 is an apocalyptic number.

It is an amenable number.

18911457 is a deficient number, since it is larger than the sum of its proper divisors (9286687).

18911457 is a wasteful number, since it uses less digits than its factorization.

18911457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67820 (or 67817 counting only the distinct ones).

The product of its digits is 10080, while the sum is 36.

The square root of 18911457 is about 4348.7305044116. The cubic root of 18911457 is about 266.4250135456.

The spelling of 18911457 in words is "eighteen million, nine hundred eleven thousand, four hundred fifty-seven".