121221020200021 has 48 divisors (see below), whose sum is σ = 145383624126720. Its totient is φ = 100717309754880.

The previous prime is 121221020199953. The next prime is 121221020200061. The reversal of 121221020200021 is 120002020122121.

It is a happy number.

It is not a de Polignac number, because 121221020200021 - 2³⁵ = 121186660461653 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121221020199968 and 121221020200004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221020200061) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 212421945 + ... + 212991841.

It is an arithmetic number, because the mean of its divisors is an integer number (3028825502640).

Almost surely, 2^{121221020200021} is an apocalyptic number.

It is an amenable number.

121221020200021 is a deficient number, since it is larger than the sum of its proper divisors (24162603926699).

121221020200021 is a wasteful number, since it uses less digits than its factorization.

121221020200021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570634 (or 570627 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 121221020200021 its reverse (120002020122121), we get a palindrome (241223040322142).

The spelling of 121221020200021 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, twenty million, two hundred thousand, twenty-one".