18290549 has 4 divisors (see below), whose sum is σ = 18316236. Its totient is φ = 18264864.

The previous prime is 18290539. The next prime is 18290557. The reversal of 18290549 is 94509281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 94509281 = 251 ⋅376531.

It can be written as a sum of positive squares in 2 ways, for example, as 16144324 + 2146225 = 4018^2 + 1465^2 .

It is a cyclic number.

It is not a de Polignac number, because 18290549 - 2⁴ = 18290533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18290539) 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, 11744 + ... + 13209.

It is an arithmetic number, because the mean of its divisors is an integer number (4579059).

Almost surely, 2^18290549 is an apocalyptic number.

It is an amenable number.

18290549 is a deficient number, since it is larger than the sum of its proper divisors (25687).

18290549 is an equidigital number, since it uses as much as digits as its factorization.

18290549 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25686.

The product of its (nonzero) digits is 25920, while the sum is 38.

The square root of 18290549 is about 4276.7451408752. The cubic root of 18290549 is about 263.4767192554.

The spelling of 18290549 in words is "eighteen million, two hundred ninety thousand, five hundred forty-nine".