131221204 has 12 divisors (see below), whose sum is σ = 230218324. Its totient is φ = 65444544.

The previous prime is 131221193. The next prime is 131221213. The reversal of 131221204 is 402122131.

131221204 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 85008400 + 46212804 = 9220^2 + 6798^2 .

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, 39729 + ... + 42904.

Almost surely, 2^131221204 is an apocalyptic number.

It is an amenable number.

131221204 is a deficient number, since it is larger than the sum of its proper divisors (98997120).

131221204 is a wasteful number, since it uses less digits than its factorization.

131221204 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83034 (or 83032 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 131221204 is about 11455.1824079759. The cubic root of 131221204 is about 508.1610097849.

Adding to 131221204 its reverse (402122131), we get a palindrome (533343335).

The spelling of 131221204 in words is "one hundred thirty-one million, two hundred twenty-one thousand, two hundred four".