18180840 has 32 divisors (see below), whose sum is σ = 54542880. Its totient is φ = 4848192.

The previous prime is 18180817. The next prime is 18180863. The reversal of 18180840 is 4808181.

It is an interprime number because it is at equal distance from previous prime (18180817) and next prime (18180863).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18180798 and 18180807.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75634 + ... + 75873.

It is an arithmetic number, because the mean of its divisors is an integer number (1704465).

Almost surely, 2^18180840 is an apocalyptic number.

18180840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18180840 is an abundant number, since it is smaller than the sum of its proper divisors (36362040).

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

18180840 is a wasteful number, since it uses less digits than its factorization.

18180840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151521 (or 151517 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 18180840 is about 4263.8996235840. The cubic root of 18180840 is about 262.9488737140.

The spelling of 18180840 in words is "eighteen million, one hundred eighty thousand, eight hundred forty".