18051780 has 96 divisors (see below), whose sum is σ = 53673984. Its totient is φ = 4523904.

The previous prime is 18051769. The next prime is 18051793. The reversal of 18051780 is 8715081.

It is a super-2 number, since 2×18051780² = 651733522336800, which contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 142077 + ... + 142203.

It is an arithmetic number, because the mean of its divisors is an integer number (559104).

Almost surely, 2^18051780 is an apocalyptic number.

18051780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18051780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26836992).

18051780 is an abundant number, since it is smaller than the sum of its proper divisors (35622204).

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

18051780 is a wasteful number, since it uses less digits than its factorization.

18051780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265 (or 263 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 30.

The square root of 18051780 is about 4248.7386363484. The cubic root of 18051780 is about 262.3251988169.

The spelling of 18051780 in words is "eighteen million, fifty-one thousand, seven hundred eighty".