1221021313212 has 24 divisors (see below), whose sum is σ = 2849106413776. Its totient is φ = 406999006848.

The previous prime is 1221021313201. The next prime is 1221021313247. The reversal of 1221021313212 is 2123131201221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 367483 + ... + 1605330.

Almost surely, 2^{1221021313212} is an apocalyptic number.

1221021313212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1221021313212 is an abundant number, since it is smaller than the sum of its proper divisors (1628085100564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221021313212 is a wasteful number, since it uses less digits than its factorization.

1221021313212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2024397 (or 2024395 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

Adding to 1221021313212 its reverse (2123131201221), we get a palindrome (3344152514433).

The spelling of 1221021313212 in words is "one trillion, two hundred twenty-one billion, twenty-one million, three hundred thirteen thousand, two hundred twelve".