131581920 has 96 divisors (see below), whose sum is σ = 416078208. Its totient is φ = 34953728.

The previous prime is 131581907. The next prime is 131581927. The reversal of 131581920 is 29185131.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131581927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 223867 + ... + 224453.

It is an arithmetic number, because the mean of its divisors is an integer number (4334148).

Almost surely, 2^131581920 is an apocalyptic number.

131581920 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 131581920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (208039104).

131581920 is an abundant number, since it is smaller than the sum of its proper divisors (284496288).

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

131581920 is a wasteful number, since it uses less digits than its factorization.

131581920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1072 (or 1064 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 30.

The square root of 131581920 is about 11470.9162668028. The cubic root of 131581920 is about 508.6262143323.

The spelling of 131581920 in words is "one hundred thirty-one million, five hundred eighty-one thousand, nine hundred twenty".