18309140 has 24 divisors (see below), whose sum is σ = 38624040. Its totient is φ = 7290368.

The previous prime is 18309131. The next prime is 18309143. The reversal of 18309140 is 4190381.

It can be written as a sum of positive squares in 4 ways, for example, as 24964 + 18284176 = 158^2 + 4276^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18309143) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2696 + ... + 6624.

It is an arithmetic number, because the mean of its divisors is an integer number (1609335).

Almost surely, 2^18309140 is an apocalyptic number.

18309140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18309140 is an abundant number, since it is smaller than the sum of its proper divisors (20314900).

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

18309140 is a wasteful number, since it uses less digits than its factorization.

18309140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4171 (or 4169 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 18309140 is about 4278.9180875544. The cubic root of 18309140 is about 263.5659572737.

The spelling of 18309140 in words is "eighteen million, three hundred nine thousand, one hundred forty".