121211221122021 has 4 divisors (see below), whose sum is σ = 161614961496032. Its totient is φ = 80807480748012.

The previous prime is 121211221121993. The next prime is 121211221122071. The reversal of 121211221122021 is 120221122112121.

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 not a de Polignac number, because 121211221122021 - 2¹¹ = 121211221119973 is a prime.

It is a super-2 number, since 2×121211221122021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211221122071) 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, 20201870187001 + ... + 20201870187006.

It is an arithmetic number, because the mean of its divisors is an integer number (40403740374008).

Almost surely, 2^{121211221122021} is an apocalyptic number.

It is an amenable number.

121211221122021 is a deficient number, since it is larger than the sum of its proper divisors (40403740374011).

121211221122021 is an equidigital number, since it uses as much as digits as its factorization.

121211221122021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40403740374010.

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

Adding to 121211221122021 its reverse (120221122112121), we get a palindrome (241432343234142).

The spelling of 121211221122021 in words is "one hundred twenty-one trillion, two hundred eleven billion, two hundred twenty-one million, one hundred twenty-two thousand, twenty-one".