115781820 has 192 divisors, whose sum is σ = 425779200. Its totient is φ = 22775040.

The previous prime is 115781803. The next prime is 115781903. The reversal of 115781820 is 28187511.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 87121 + ... + 88439.

It is an arithmetic number, because the mean of its divisors is an integer number (2217600).

Almost surely, 2^115781820 is an apocalyptic number.

115781820 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 115781820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (212889600).

115781820 is an abundant number, since it is smaller than the sum of its proper divisors (309997380).

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

115781820 is a wasteful number, since it uses less digits than its factorization.

115781820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1368 (or 1366 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 33.

The square root of 115781820 is about 10760.1960948674. The cubic root of 115781820 is about 487.3939387940.

The spelling of 115781820 in words is "one hundred fifteen million, seven hundred eighty-one thousand, eight hundred twenty".