1312204221 has 48 divisors (see below), whose sum is σ = 1982857968. Its totient is φ = 835584000.

The previous prime is 1312204213. The next prime is 1312204247. The reversal of 1312204221 is 1224022131.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 185259321 + 1126944900 = 13611^2 + 33570^2 .

It is not a de Polignac number, because 1312204221 - 2³ = 1312204213 is a prime.

It is a super-2 number, since 2×1312204221² = 3443759835220433682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1312204194 and 1312204203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1312204291) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5105725 + ... + 5105981.

It is an arithmetic number, because the mean of its divisors is an integer number (41309541).

Almost surely, 2^1312204221 is an apocalyptic number.

It is an amenable number.

1312204221 is a deficient number, since it is larger than the sum of its proper divisors (670653747).

1312204221 is a wasteful number, since it uses less digits than its factorization.

1312204221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 542 (or 539 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 1312204221 is about 36224.3594974432. The cubic root of 1312204221 is about 1094.7975330920.

Adding to 1312204221 its reverse (1224022131), we get a palindrome (2536226352).

The spelling of 1312204221 in words is "one billion, three hundred twelve million, two hundred four thousand, two hundred twenty-one".