18128420 has 12 divisors (see below), whose sum is σ = 38069724. Its totient is φ = 7251360.

The previous prime is 18128419. The next prime is 18128441. The reversal of 18128420 is 2482181.

It can be written as a sum of positive squares in 2 ways, for example, as 6031936 + 12096484 = 2456^2 + 3478^2 .

It is a super-2 number, since 2×18128420² = 657279223392800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18128420.

It is a congruent number.

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, 453191 + ... + 453230.

It is an arithmetic number, because the mean of its divisors is an integer number (3172477).

Almost surely, 2^18128420 is an apocalyptic number.

18128420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18128420 is an abundant number, since it is smaller than the sum of its proper divisors (19941304).

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

18128420 is a wasteful number, since it uses less digits than its factorization.

18128420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 906430 (or 906428 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 26.

The square root of 18128420 is about 4257.7482311663. The cubic root of 18128420 is about 262.6959142137.

The spelling of 18128420 in words is "eighteen million, one hundred twenty-eight thousand, four hundred twenty".