2131221304 has 8 divisors (see below), whose sum is σ = 3996039960. Its totient is φ = 1065610648.

The previous prime is 2131221283. The next prime is 2131221359. The reversal of 2131221304 is 4031221312.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 133201324 + ... + 133201339.

It is an arithmetic number, because the mean of its divisors is an integer number (499504995).

Almost surely, 2^2131221304 is an apocalyptic number.

It is an amenable number.

2131221304 is a deficient number, since it is larger than the sum of its proper divisors (1864818656).

2131221304 is a wasteful number, since it uses less digits than its factorization.

2131221304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266402669 (or 266402665 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 2131221304 is about 46165.1524853975. The cubic root of 2131221304 is about 1286.8942179746.

Adding to 2131221304 its reverse (4031221312), we get a palindrome (6162442616).

The spelling of 2131221304 in words is "two billion, one hundred thirty-one million, two hundred twenty-one thousand, three hundred four".