61115904 has 80 divisors (see below), whose sum is σ = 180948240. Its totient is φ = 20367360.

The previous prime is 61115903. The next prime is 61115909. The reversal of 61115904 is 40951116.

61115904 is a `hidden beast` number, since 61 + 11 + 590 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61115903) 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, 11614 + ... + 16034.

It is an arithmetic number, because the mean of its divisors is an integer number (2261853).

Almost surely, 2^61115904 is an apocalyptic number.

61115904 is a gapful number since it is divisible by the number (64) 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 61115904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90474120).

61115904 is an abundant number, since it is smaller than the sum of its proper divisors (119832336).

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

61115904 is an equidigital number, since it uses as much as digits as its factorization.

61115904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4448 (or 4426 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 61115904 is about 7817.6661478986. Note that the first 3 decimals coincide. The cubic root of 61115904 is about 393.8988806611.

The spelling of 61115904 in words is "sixty-one million, one hundred fifteen thousand, nine hundred four".