18055550 has 12 divisors (see below), whose sum is σ = 33583416. Its totient is φ = 7222200.

The previous prime is 18055517. The next prime is 18055553. The reversal of 18055550 is 5555081.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18055553) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 180506 + ... + 180605.

It is an arithmetic number, because the mean of its divisors is an integer number (2798618).

Almost surely, 2^18055550 is an apocalyptic number.

18055550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18055550 is a deficient number, since it is larger than the sum of its proper divisors (15527866).

18055550 is a wasteful number, since it uses less digits than its factorization.

18055550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361123 (or 361118 counting only the distinct ones).

The product of its (nonzero) digits is 5000, while the sum is 29.

The square root of 18055550 is about 4249.1822742735. The cubic root of 18055550 is about 262.3434591982.

The spelling of 18055550 in words is "eighteen million, fifty-five thousand, five hundred fifty".