1221221321310 has 64 divisors (see below), whose sum is σ = 2935531694592. Its totient is φ = 325148094336.

The previous prime is 1221221321293. The next prime is 1221221321357. The reversal of 1221221321310 is 131231221221.

It is a super-2 number, since 2×1221221321310² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 167126677 + ... + 167133983.

It is an arithmetic number, because the mean of its divisors is an integer number (45867682728).

Almost surely, 2^{1221221321310} is an apocalyptic number.

1221221321310 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221221321310 is an abundant number, since it is smaller than the sum of its proper divisors (1714310373282).

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

1221221321310 is a wasteful number, since it uses less digits than its factorization.

1221221321310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15297.

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

Adding to 1221221321310 its reverse (131231221221), we get a palindrome (1352452542531).

The spelling of 1221221321310 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, three hundred twenty-one thousand, three hundred ten".