1156561120 has 96 divisors (see below), whose sum is σ = 3210127200. Its totient is φ = 388208640.

The previous prime is 1156561117. The next prime is 1156561139. The reversal of 1156561120 is 211656511.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2395 + ... + 48154.

It is an arithmetic number, because the mean of its divisors is an integer number (33438825).

Almost surely, 2^1156561120 is an apocalyptic number.

1156561120 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 1156561120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1605063600).

1156561120 is an abundant number, since it is smaller than the sum of its proper divisors (2053566080).

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

1156561120 is a wasteful number, since it uses less digits than its factorization.

1156561120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50588 (or 50580 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 28.

The square root of 1156561120 is about 34008.2507636015. The cubic root of 1156561120 is about 1049.6782445728.

The spelling of 1156561120 in words is "one billion, one hundred fifty-six million, five hundred sixty-one thousand, one hundred twenty".