18007428 has 12 divisors (see below), whose sum is σ = 42017360. Its totient is φ = 6002472.

The previous prime is 18007361. The next prime is 18007447. The reversal of 18007428 is 82470081.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 18007395 and 18007404.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 750298 + ... + 750321.

Almost surely, 2^18007428 is an apocalyptic number.

It is an amenable number.

18007428 is an abundant number, since it is smaller than the sum of its proper divisors (24009932).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18007428 is a wasteful number, since it uses less digits than its factorization.

18007428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1500626 (or 1500624 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 18007428 is about 4243.5159950211. The cubic root of 18007428 is about 262.1101842170.

The spelling of 18007428 in words is "eighteen million, seven thousand, four hundred twenty-eight".