18011880 has 48 divisors (see below), whose sum is σ = 58539780. Its totient is φ = 4803072.

The previous prime is 18011879. The next prime is 18011881. The reversal of 18011880 is 8811081.

It is an interprime number because it is at equal distance from previous prime (18011879) and next prime (18011881).

It can be written as a sum of positive squares in 2 ways, for example, as 15634116 + 2377764 = 3954^2 + 1542^2 .

It is a super-2 number, since 2×18011880² = 648855642268800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18011881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24657 + ... + 25376.

Almost surely, 2^18011880 is an apocalyptic number.

18011880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18011880 is an abundant number, since it is smaller than the sum of its proper divisors (40527900).

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

18011880 is a wasteful number, since it uses less digits than its factorization.

18011880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50050 (or 50043 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 27.

The square root of 18011880 is about 4244.0405276105. The cubic root of 18011880 is about 262.1317830518.

The spelling of 18011880 in words is "eighteen million, eleven thousand, eight hundred eighty".