18870428 has 6 divisors (see below), whose sum is σ = 33023256. Its totient is φ = 9435212.

The previous prime is 18870389. The next prime is 18870469. The reversal of 18870428 is 82407881.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 18870391 and 18870400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2358800 + ... + 2358807.

It is an arithmetic number, because the mean of its divisors is an integer number (5503876).

Almost surely, 2^18870428 is an apocalyptic number.

It is an amenable number.

18870428 is a deficient number, since it is larger than the sum of its proper divisors (14152828).

18870428 is a wasteful number, since it uses less digits than its factorization.

18870428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4717611 (or 4717609 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 38.

The square root of 18870428 is about 4344.0105893057. The cubic root of 18870428 is about 266.2322015625.

The spelling of 18870428 in words is "eighteen million, eight hundred seventy thousand, four hundred twenty-eight".