131821920 has 144 divisors (see below), whose sum is σ = 464510592. Its totient is φ = 34007040.

The previous prime is 131821913. The next prime is 131821969. The reversal of 131821920 is 29128131.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 43164 + ... + 46116.

It is an arithmetic number, because the mean of its divisors is an integer number (3225768).

Almost surely, 2^131821920 is an apocalyptic number.

131821920 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 131821920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (232255296).

131821920 is an abundant number, since it is smaller than the sum of its proper divisors (332688672).

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

131821920 is a wasteful number, since it uses less digits than its factorization.

131821920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3005 (or 2994 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 131821920 is about 11481.3727402258. The cubic root of 131821920 is about 508.9352642623.

The spelling of 131821920 in words is "one hundred thirty-one million, eight hundred twenty-one thousand, nine hundred twenty".