1221882881221 has 4 divisors (see below), whose sum is σ = 1222228733292. Its totient is φ = 1221537029152.

The previous prime is 1221882881201. The next prime is 1221882881239.

It is a happy number.

1221882881221 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 635027296996 + 586855584225 = 796886^2 + 766065^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221882881221 - 2³⁵ = 1187523142853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221882881201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172920736 + ... + 172927801.

It is an arithmetic number, because the mean of its divisors is an integer number (305557183323).

Almost surely, 2^{1221882881221} is an apocalyptic number.

It is an amenable number.

1221882881221 is a deficient number, since it is larger than the sum of its proper divisors (345852071).

1221882881221 is an equidigital number, since it uses as much as digits as its factorization.

1221882881221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 345852070.

The product of its digits is 131072, while the sum is 46.

The spelling of 1221882881221 in words is "one trillion, two hundred twenty-one billion, eight hundred eighty-two million, eight hundred eighty-one thousand, two hundred twenty-one".