18135780 has 48 divisors (see below), whose sum is σ = 54688704. Its totient is φ = 4464000.

The previous prime is 18135773. The next prime is 18135781. The reversal of 18135780 is 8753181.

It is not an unprimeable number, because it can be changed into a prime (18135781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10846 + ... + 12405.

It is an arithmetic number, because the mean of its divisors is an integer number (1139348).

Almost surely, 2^18135780 is an apocalyptic number.

18135780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18135780 is an abundant number, since it is smaller than the sum of its proper divisors (36552924).

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

18135780 is a wasteful number, since it uses less digits than its factorization.

18135780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23276 (or 23274 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 33.

The square root of 18135780 is about 4258.6124500828. The cubic root of 18135780 is about 262.7314602483.

It can be divided in two parts, 18135 and 780, that added together give a triangular number (18915 = T₁₉₄).

The spelling of 18135780 in words is "eighteen million, one hundred thirty-five thousand, seven hundred eighty".