18271840 has 24 divisors (see below), whose sum is σ = 43167600. Its totient is φ = 7308672.

The previous prime is 18271819. The next prime is 18271849. The reversal of 18271840 is 4817281.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18271849) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 56940 + ... + 57259.

It is an arithmetic number, because the mean of its divisors is an integer number (1798650).

Almost surely, 2^18271840 is an apocalyptic number.

18271840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18271840 is an abundant number, since it is smaller than the sum of its proper divisors (24895760).

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

18271840 is a wasteful number, since it uses less digits than its factorization.

18271840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114214 (or 114206 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 18271840 is about 4274.5572870182. The cubic root of 18271840 is about 263.3868537623.

The spelling of 18271840 in words is "eighteen million, two hundred seventy-one thousand, eight hundred forty".