131221133 has 16 divisors (see below), whose sum is σ = 138240000. Its totient is φ = 124446192.

The previous prime is 131221121. The next prime is 131221151. The reversal of 131221133 is 331122131.

It is a cyclic number.

It is not a de Polignac number, because 131221133 - 2⁴ = 131221117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131221183) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 218768 + ... + 219366.

It is an arithmetic number, because the mean of its divisors is an integer number (8640000).

Almost surely, 2^131221133 is an apocalyptic number.

It is an amenable number.

131221133 is a deficient number, since it is larger than the sum of its proper divisors (7018867).

131221133 is an equidigital number, since it uses as much as digits as its factorization.

131221133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 784.

The product of its digits is 108, while the sum is 17.

The square root of 131221133 is about 11455.1793089414. The cubic root of 131221133 is about 508.1609181345.

Adding to 131221133 its reverse (331122131), we get a palindrome (462343264).

The spelling of 131221133 in words is "one hundred thirty-one million, two hundred twenty-one thousand, one hundred thirty-three".