121221020202020 has 96 divisors (see below), whose sum is σ = 267339817785600. Its totient is φ = 46110767650304.

The previous prime is 121221020202019. The next prime is 121221020202047. The reversal of 121221020202020 is 20202020122121.

It is a happy number.

It is a super-2 number, since 2×121221020202020² (a number of 29 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121221020202020.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5091041 + ... + 16381719.

It is an arithmetic number, because the mean of its divisors is an integer number (2784789768600).

Almost surely, 2^{121221020202020} is an apocalyptic number.

121221020202020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121221020202020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (133669908892800).

121221020202020 is an abundant number, since it is smaller than the sum of its proper divisors (146118797583580).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121221020202020 is a wasteful number, since it uses less digits than its factorization.

121221020202020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11290997 (or 11290995 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 121221020202020 its reverse (20202020122121), we get a palindrome (141423040324141).

The spelling of 121221020202020 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, twenty million, two hundred two thousand, twenty".