18006554 has 4 divisors (see below), whose sum is σ = 27009834. Its totient is φ = 9003276.

The previous prime is 18006497. The next prime is 18006557. The reversal of 18006554 is 45560081.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 13490929 + 4515625 = 3673^2 + 2125^2 .

It is not an unprimeable number, because it can be changed into a prime (18006557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4501637 + ... + 4501640.

Almost surely, 2^18006554 is an apocalyptic number.

18006554 is a deficient number, since it is larger than the sum of its proper divisors (9003280).

18006554 is an equidigital number, since it uses as much as digits as its factorization.

18006554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9003279.

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 18006554 is about 4243.4130131299. The cubic root of 18006554 is about 262.1059435965.

The spelling of 18006554 in words is "eighteen million, six thousand, five hundred fifty-four".