131221125 has 96 divisors (see below), whose sum is σ = 284893440. Its totient is φ = 56764800.

The previous prime is 131221121. The next prime is 131221151. The reversal of 131221125 is 521122131.

It is not a de Polignac number, because 131221125 - 2² = 131221121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 131221098 and 131221107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131221121) 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 95 ways as a sum of consecutive naturals, for example, 149187 + ... + 150063.

It is an arithmetic number, because the mean of its divisors is an integer number (2967640).

Almost surely, 2^131221125 is an apocalyptic number.

131221125 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

131221125 is an abundant number, since it is smaller than the sum of its proper divisors (153672315).

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

131221125 is a wasteful number, since it uses less digits than its factorization.

131221125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 924 (or 911 counting only the distinct ones).

The product of its digits is 120, while the sum is 18.

The square root of 131221125 is about 11455.1789597544. The cubic root of 131221125 is about 508.1609078077.

Adding to 131221125 its reverse (521122131), we get a palindrome (652343256).

The spelling of 131221125 in words is "one hundred thirty-one million, two hundred twenty-one thousand, one hundred twenty-five".