131231940 has 96 divisors (see below), whose sum is σ = 422682624. Its totient is φ = 29800320.

The previous prime is 131231929. The next prime is 131231941. The reversal of 131231940 is 49132131.

It is a self number, because there is not a number n which added to its sum of digits gives 131231940.

It is not an unprimeable number, because it can be changed into a prime (131231941) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 69205 + ... + 71075.

It is an arithmetic number, because the mean of its divisors is an integer number (4402944).

Almost surely, 2^131231940 is an apocalyptic number.

131231940 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 131231940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (211341312).

131231940 is an abundant number, since it is smaller than the sum of its proper divisors (291450684).

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

131231940 is a wasteful number, since it uses less digits than its factorization.

131231940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2057 (or 2055 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 24.

The square root of 131231940 is about 11455.6510072540. The cubic root of 131231940 is about 508.1748679818.

The spelling of 131231940 in words is "one hundred thirty-one million, two hundred thirty-one thousand, nine hundred forty".