18040140 has 144 divisors (see below), whose sum is σ = 58496256. Its totient is φ = 4492800.

The previous prime is 18040129. The next prime is 18040147. The reversal of 18040140 is 4104081.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (18040147) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 295710 + ... + 295770.

It is an arithmetic number, because the mean of its divisors is an integer number (406224).

Almost surely, 2^18040140 is an apocalyptic number.

18040140 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 18040140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29248128).

18040140 is an abundant number, since it is smaller than the sum of its proper divisors (40456116).

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

18040140 is a wasteful number, since it uses less digits than its factorization.

18040140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 160 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 18040140 is about 4247.3685971434. The cubic root of 18040140 is about 262.2688032361.

The spelling of 18040140 in words is "eighteen million, forty thousand, one hundred forty".