1221458541221 has 4 divisors (see below), whose sum is σ = 1222073268192. Its totient is φ = 1220843814252.

The previous prime is 1221458541211. The next prime is 1221458541253.

1221458541221 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1221458541221 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 (1221458541211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 307360505 + ... + 307364478.

It is an arithmetic number, because the mean of its divisors is an integer number (305518317048).

Almost surely, 2^{1221458541221} is an apocalyptic number.

It is an amenable number.

1221458541221 is a deficient number, since it is larger than the sum of its proper divisors (614726971).

1221458541221 is an equidigital number, since it uses as much as digits as its factorization.

1221458541221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614726970.

The product of its digits is 51200, while the sum is 38.

The spelling of 1221458541221 in words is "one trillion, two hundred twenty-one billion, four hundred fifty-eight million, five hundred forty-one thousand, two hundred twenty-one".