1021113121221 has 12 divisors (see below), whose sum is σ = 1475626266348. Its totient is φ = 680425884864.

The previous prime is 1021113121199. The next prime is 1021113121243. The reversal of 1021113121221 is 1221213111201.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1021113121199) and next prime (1021113121243).

It can be written as a sum of positive squares in 2 ways, for example, as 624477677121 + 396635444100 = 790239^2 + 629790^2 .

It is not a de Polignac number, because 1021113121221 - 2¹⁰ = 1021113120197 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1021113121194 and 1021113121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021113121621) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 26329210 + ... + 26367963.

It is an arithmetic number, because the mean of its divisors is an integer number (122968855529).

Almost surely, 2^{1021113121221} is an apocalyptic number.

It is an amenable number.

1021113121221 is a deficient number, since it is larger than the sum of its proper divisors (454513145127).

1021113121221 is a wasteful number, since it uses less digits than its factorization.

1021113121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52699332 (or 52699329 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 18.

Adding to 1021113121221 its reverse (1221213111201), we get a palindrome (2242326232422).

The spelling of 1021113121221 in words is "one trillion, twenty-one billion, one hundred thirteen million, one hundred twenty-one thousand, two hundred twenty-one".