121211021020 has 96 divisors (see below), whose sum is σ = 280425499200. Its totient is φ = 43803561984.

The previous prime is 121211021011. The next prime is 121211021021. The reversal of 121211021020 is 20120112121.

It is a super-2 number, since 2×121211021020² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121211021021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1670251 + ... + 1741309.

It is an arithmetic number, because the mean of its divisors is an integer number (2921098950).

Almost surely, 2^121211021020 is an apocalyptic number.

121211021020 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 121211021020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140212749600).

121211021020 is an abundant number, since it is smaller than the sum of its proper divisors (159214478180).

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

121211021020 is a wasteful number, since it uses less digits than its factorization.

121211021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71287 (or 71285 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 121211021020 its reverse (20120112121), we get a palindrome (141331133141).

The spelling of 121211021020 in words is "one hundred twenty-one billion, two hundred eleven million, twenty-one thousand, twenty".