1161139920 has 160 divisors (see below), whose sum is σ = 3719464320. Its totient is φ = 299427840.

The previous prime is 1161139897. The next prime is 1161139921. The reversal of 1161139920 is 299311611.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1161139921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2033235 + ... + 2033805.

It is an arithmetic number, because the mean of its divisors is an integer number (23246652).

Almost surely, 2^1161139920 is an apocalyptic number.

1161139920 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 1161139920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1859732160).

1161139920 is an abundant number, since it is smaller than the sum of its proper divisors (2558324400).

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

1161139920 is a wasteful number, since it uses less digits than its factorization.

1161139920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 853 (or 847 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 33.

The square root of 1161139920 is about 34075.5032244573. The cubic root of 1161139920 is about 1051.0616382509.

The spelling of 1161139920 in words is "one billion, one hundred sixty-one million, one hundred thirty-nine thousand, nine hundred twenty".