131991120 has 100 divisors (see below), whose sum is σ = 458447220. Its totient is φ = 35195904.

The previous prime is 131991109. The next prime is 131991133. The reversal of 131991120 is 21199131.

It can be written as a sum of positive squares in 2 ways, for example, as 70963776 + 61027344 = 8424^2 + 7812^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3705 + ... + 16664.

Almost surely, 2^131991120 is an apocalyptic number.

131991120 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 131991120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229223610).

131991120 is an abundant number, since it is smaller than the sum of its proper divisors (326456100).

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

131991120 is a wasteful number, since it uses less digits than its factorization.

131991120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20394 (or 20379 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 27.

The square root of 131991120 is about 11488.7388341802. The cubic root of 131991120 is about 509.1529190854.

The spelling of 131991120 in words is "one hundred thirty-one million, nine hundred ninety-one thousand, one hundred twenty".