131231228 has 12 divisors (see below), whose sum is σ = 243163872. Its totient is φ = 61755840.

The previous prime is 131231213. The next prime is 131231237. The reversal of 131231228 is 822132131.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 964868 + ... + 965003.

It is an arithmetic number, because the mean of its divisors is an integer number (20263656).

Almost surely, 2^131231228 is an apocalyptic number.

It is an amenable number.

131231228 is a deficient number, since it is larger than the sum of its proper divisors (111932644).

131231228 is a wasteful number, since it uses less digits than its factorization.

131231228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1929892 (or 1929890 counting only the distinct ones).

The product of its digits is 576, while the sum is 23.

The square root of 131231228 is about 11455.6199308462. The cubic root of 131231228 is about 508.1739489444.

Adding to 131231228 its reverse (822132131), we get a palindrome (953363359).

The spelling of 131231228 in words is "one hundred thirty-one million, two hundred thirty-one thousand, two hundred twenty-eight".