18871497 has 12 divisors (see below), whose sum is σ = 27510340. Its totient is φ = 12464928.

The previous prime is 18871481. The next prime is 18871499. The reversal of 18871497 is 79417881.

It can be written as a sum of positive squares in 2 ways, for example, as 7338681 + 11532816 = 2709^2 + 3396^2 .

It is not a de Polignac number, because 18871497 - 2⁴ = 18871481 is a prime.

It is a super-2 number, since 2×18871497² = 712266798042018, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18871499) 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, 8638 + ... + 10599.

Almost surely, 2^18871497 is an apocalyptic number.

It is an amenable number.

18871497 is a deficient number, since it is larger than the sum of its proper divisors (8638843).

18871497 is a wasteful number, since it uses less digits than its factorization.

18871497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19352 (or 19349 counting only the distinct ones).

The product of its digits is 112896, while the sum is 45.

The square root of 18871497 is about 4344.1336305413. The cubic root of 18871497 is about 266.2372287731.

The spelling of 18871497 in words is "eighteen million, eight hundred seventy-one thousand, four hundred ninety-seven".