121111221222021 has 16 divisors (see below), whose sum is σ = 169983162455040. Its totient is φ = 76490172123120.

The previous prime is 121111221222001. The next prime is 121111221222023. The reversal of 121111221222021 is 120222122111121.

It is not a de Polignac number, because 121111221222021 - 2⁶ = 121111221221957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121111221222023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11715435 + ... + 19480088.

It is an arithmetic number, because the mean of its divisors is an integer number (10623947653440).

Almost surely, 2^{121111221222021} is an apocalyptic number.

It is an amenable number.

121111221222021 is a deficient number, since it is larger than the sum of its proper divisors (48871941233019).

121111221222021 is a wasteful number, since it uses less digits than its factorization.

121111221222021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31263656.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 121111221222021 its reverse (120222122111121), we get a palindrome (241333343333142).

The spelling of 121111221222021 in words is "one hundred twenty-one trillion, one hundred eleven billion, two hundred twenty-one million, two hundred twenty-two thousand, twenty-one".