1212313221 has 48 divisors (see below), whose sum is σ = 2114112000. Its totient is φ = 653953824.

The previous prime is 1212313217. The next prime is 1212313229. The reversal of 1212313221 is 1223132121.

It is not a de Polignac number, because 1212313221 - 2² = 1212313217 is a prime.

It is a super-2 number, since 2×1212313221² = 2939406691622789682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1212313194 and 1212313203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212313229) 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, 365830 + ... + 369128.

It is an arithmetic number, because the mean of its divisors is an integer number (44044000).

Almost surely, 2^1212313221 is an apocalyptic number.

It is an amenable number.

1212313221 is a deficient number, since it is larger than the sum of its proper divisors (901798779).

1212313221 is a wasteful number, since it uses less digits than its factorization.

1212313221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3638 (or 3635 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 1212313221 is about 34818.2885995277. The cubic root of 1212313221 is about 1066.2808605493.

Adding to 1212313221 its reverse (1223132121), we get a palindrome (2435445342).

The spelling of 1212313221 in words is "one billion, two hundred twelve million, three hundred thirteen thousand, two hundred twenty-one".