18197489 has 4 divisors (see below), whose sum is σ = 18306624. Its totient is φ = 18088356.

The previous prime is 18197453. The next prime is 18197549. The reversal of 18197489 is 98479181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 98479181 = 17 ⋅5792893.

It is a cyclic number.

It is not a de Polignac number, because 18197489 - 2²⁰ = 17148913 is a prime.

It is a super-2 number, since 2×18197489² = 662297211810242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18197419) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54317 + ... + 54650.

It is an arithmetic number, because the mean of its divisors is an integer number (4576656).

Almost surely, 2^18197489 is an apocalyptic number.

It is an amenable number.

18197489 is a deficient number, since it is larger than the sum of its proper divisors (109135).

18197489 is a wasteful number, since it uses less digits than its factorization.

18197489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109134.

The product of its digits is 145152, while the sum is 47.

The square root of 18197489 is about 4265.8514976497. The cubic root of 18197489 is about 263.0291138670.

The spelling of 18197489 in words is "eighteen million, one hundred ninety-seven thousand, four hundred eighty-nine".