131321621 has 8 divisors (see below), whose sum is σ = 136581120. Its totient is φ = 126152208.

The previous prime is 131321581. The next prime is 131321627. The reversal of 131321621 is 126123131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131321621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 131321593 and 131321602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131321627) 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 7 ways as a sum of consecutive naturals, for example, 19541 + ... + 25386.

It is an arithmetic number, because the mean of its divisors is an integer number (17072640).

Almost surely, 2^131321621 is an apocalyptic number.

It is an amenable number.

131321621 is a deficient number, since it is larger than the sum of its proper divisors (5259499).

131321621 is an equidigital number, since it uses as much as digits as its factorization.

131321621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45043.

The product of its digits is 216, while the sum is 20.

The square root of 131321621 is about 11459.5646077851. The cubic root of 131321621 is about 508.2906001045.

Adding to 131321621 its reverse (126123131), we get a palindrome (257444752).

The spelling of 131321621 in words is "one hundred thirty-one million, three hundred twenty-one thousand, six hundred twenty-one".