131221144 has 32 divisors (see below), whose sum is σ = 259642800. Its totient is φ = 62000640.

The previous prime is 131221121. The next prime is 131221151. The reversal of 131221144 is 441122131.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 78364 + ... + 80020.

Almost surely, 2^131221144 is an apocalyptic number.

It is an amenable number.

131221144 is a deficient number, since it is larger than the sum of its proper divisors (128421656).

131221144 is a wasteful number, since it uses less digits than its factorization.

131221144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2203 (or 2199 counting only the distinct ones).

The product of its digits is 192, while the sum is 19.

The square root of 131221144 is about 11455.1797890736. The cubic root of 131221144 is about 508.1609323339.

Adding to 131221144 its reverse (441122131), we get a palindrome (572343275).

The spelling of 131221144 in words is "one hundred thirty-one million, two hundred twenty-one thousand, one hundred forty-four".