121221021222221 has 4 divisors (see below), whose sum is σ = 121222706159712. Its totient is φ = 121219336284732.

The previous prime is 121221021222137. The next prime is 121221021222263. The reversal of 121221021222221 is 122222120122121.

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 not a de Polignac number, because 121221021222221 - 2¹⁰ = 121221021221197 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 (121221021222421) 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, 842360825 + ... + 842504718.

It is an arithmetic number, because the mean of its divisors is an integer number (30305676539928).

Almost surely, 2^{121221021222221} is an apocalyptic number.

It is an amenable number.

121221021222221 is a deficient number, since it is larger than the sum of its proper divisors (1684937491).

121221021222221 is an equidigital number, since it uses as much as digits as its factorization.

121221021222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1684937490.

The product of its (nonzero) digits is 512, while the sum is 23.

Adding to 121221021222221 its reverse (122222120122121), we get a palindrome (243443141344342).

The spelling of 121221021222221 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, twenty-one million, two hundred twenty-two thousand, two hundred twenty-one".