18380553 has 16 divisors (see below), whose sum is σ = 26044416. Its totient is φ = 11490560.

The previous prime is 18380539. The next prime is 18380563. The reversal of 18380553 is 35508381.

It is a cyclic number.

It is not a de Polignac number, because 18380553 - 2²⁴ = 1603337 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18380563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19063 + ... + 20003.

It is an arithmetic number, because the mean of its divisors is an integer number (1627776).

Almost surely, 2^18380553 is an apocalyptic number.

It is an amenable number.

18380553 is a deficient number, since it is larger than the sum of its proper divisors (7663863).

18380553 is a wasteful number, since it uses less digits than its factorization.

18380553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1344.

The product of its (nonzero) digits is 14400, while the sum is 33.

The square root of 18380553 is about 4287.2547160158. The cubic root of 18380553 is about 263.9081837506.

The spelling of 18380553 in words is "eighteen million, three hundred eighty thousand, five hundred fifty-three".