18195840 has 256 divisors, whose sum is σ = 70257600. Its totient is φ = 4478976.

The previous prime is 18195839. The next prime is 18195851. The reversal of 18195840 is 4859181.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 18195795 and 18195804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1399674 + ... + 1399686.

Almost surely, 2^18195840 is an apocalyptic number.

18195840 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 18195840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35128800).

18195840 is an abundant number, since it is smaller than the sum of its proper divisors (52061760).

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

18195840 is an frugal number, since it uses more digits than its factorization.

18195840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53 (or 23 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 18195840 is about 4265.6582141564. The cubic root of 18195840 is about 263.0211686663.

The spelling of 18195840 in words is "eighteen million, one hundred ninety-five thousand, eight hundred forty".