18988459 has 4 divisors (see below), whose sum is σ = 21701104. Its totient is φ = 16275816.

The previous prime is 18988421. The next prime is 18988471. The reversal of 18988459 is 95488981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 95488981 = 7 ⋅13641283.

It is a cyclic number.

It is not a de Polignac number, because 18988459 - 2⁷ = 18988331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18908459) 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, 1356312 + ... + 1356325.

It is an arithmetic number, because the mean of its divisors is an integer number (5425276).

Almost surely, 2^18988459 is an apocalyptic number.

18988459 is a deficient number, since it is larger than the sum of its proper divisors (2712645).

18988459 is an equidigital number, since it uses as much as digits as its factorization.

18988459 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2712644.

The product of its digits is 829440, while the sum is 52.

The square root of 18988459 is about 4357.5748989547. The cubic root of 18988459 is about 266.7861258180.

The spelling of 18988459 in words is "eighteen million, nine hundred eighty-eight thousand, four hundred fifty-nine".