131221340 has 48 divisors (see below), whose sum is σ = 281407392. Its totient is φ = 51388416.

The previous prime is 131221339. The next prime is 131221379. The reversal of 131221340 is 43122131.

131221340 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 227132 + ... + 227708.

It is an arithmetic number, because the mean of its divisors is an integer number (5862654).

Almost surely, 2^131221340 is an apocalyptic number.

131221340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

131221340 is an abundant number, since it is smaller than the sum of its proper divisors (150186052).

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

131221340 is a wasteful number, since it uses less digits than its factorization.

131221340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 806 (or 804 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 131221340 is about 11455.1883441522. The cubic root of 131221340 is about 508.1611853406.

Adding to 131221340 its reverse (43122131), we get a palindrome (174343471).

The spelling of 131221340 in words is "one hundred thirty-one million, two hundred twenty-one thousand, three hundred forty".