61109144320 has 432 divisors, whose sum is σ = 177703593984. Its totient is φ = 19713024000.

The previous prime is 61109144309. The next prime is 61109144323. The reversal of 61109144320 is 2344190116.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is not an unprimeable number, because it can be changed into a prime (61109144323) 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, 404696245 + ... + 404696395.

It is an arithmetic number, because the mean of its divisors is an integer number (411350912).

Almost surely, 2^61109144320 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61109144320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (88851796992).

61109144320 is an abundant number, since it is smaller than the sum of its proper divisors (116594449664).

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

61109144320 is a wasteful number, since it uses less digits than its factorization.

61109144320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288 (or 243 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 31.

The spelling of 61109144320 in words is "sixty-one billion, one hundred nine million, one hundred forty-four thousand, three hundred twenty".