1020120021121 has 4 divisors (see below), whose sum is σ = 1020124620100. Its totient is φ = 1020115422144.

The previous prime is 1020120021077. The next prime is 1020120021127. The reversal of 1020120021121 is 1211200210201.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 889249000000 + 130871021121 = 943000^2 + 361761^2 .

It is a cyclic number.

It is not a de Polignac number, because 1020120021121 - 2³³ = 1011530086529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1020120021127) 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, 1948956 + ... + 2416333.

It is an arithmetic number, because the mean of its divisors is an integer number (255031155025).

Almost surely, 2^{1020120021121} is an apocalyptic number.

It is an amenable number.

1020120021121 is a deficient number, since it is larger than the sum of its proper divisors (4598979).

1020120021121 is an equidigital number, since it uses as much as digits as its factorization.

1020120021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4598978.

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

Adding to 1020120021121 its reverse (1211200210201), we get a palindrome (2231320231322).

The spelling of 1020120021121 in words is "one trillion, twenty billion, one hundred twenty million, twenty-one thousand, one hundred twenty-one".