121221111021 has 8 divisors (see below), whose sum is σ = 161937190560. Its totient is φ = 80659552752.

The previous prime is 121221110993. The next prime is 121221111043. The reversal of 121221111021 is 120111122121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121221111021 - 2⁶ = 121221110957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221111091) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38628486 + ... + 38631623.

It is an arithmetic number, because the mean of its divisors is an integer number (20242148820).

Almost surely, 2^121221111021 is an apocalyptic number.

It is an amenable number.

121221111021 is a deficient number, since it is larger than the sum of its proper divisors (40716079539).

121221111021 is an equidigital number, since it uses as much as digits as its factorization.

121221111021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77260635.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 121221111021 its reverse (120111122121), we get a palindrome (241332233142).

The spelling of 121221111021 in words is "one hundred twenty-one billion, two hundred twenty-one million, one hundred eleven thousand, twenty-one".