18131585400 has 192 divisors, whose sum is σ = 65169043200. Its totient is φ = 4624836480.

The previous prime is 18131585387. The next prime is 18131585429. The reversal of 18131585400 is 458513181.

18131585400 is a `hidden beast` number, since 1 + 8 + 1 + 31 + 585 + 40 + 0 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 51207 + ... + 197193.

It is an arithmetic number, because the mean of its divisors is an integer number (339422100).

Almost surely, 2^18131585400 is an apocalyptic number.

18131585400 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 18131585400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32584521600).

18131585400 is an abundant number, since it is smaller than the sum of its proper divisors (47037457800).

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

18131585400 is a wasteful number, since it uses less digits than its factorization.

18131585400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146035 (or 146020 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

The spelling of 18131585400 in words is "eighteen billion, one hundred thirty-one million, five hundred eighty-five thousand, four hundred".