1121212121021 has 6 divisors (see below), whose sum is σ = 1145575265790. Its totient is φ = 1097356541816.

The previous prime is 1121212121017. The next prime is 1121212121033. The reversal of 1121212121021 is 1201212121211.

It can be written as a sum of positive squares in only one way, i.e., 1115822505625 + 5389615396 = 1056325^2 + 73414^2 .

It is not a de Polignac number, because 1121212121021 - 2² = 1121212121017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121212121041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 253780526 + ... + 253784943.

It is an arithmetic number, because the mean of its divisors is an integer number (190929210965).

Almost surely, 2^{1121212121021} is an apocalyptic number.

It is an amenable number.

1121212121021 is a deficient number, since it is larger than the sum of its proper divisors (24363144769).

1121212121021 is an frugal number, since it uses more digits than its factorization.

1121212121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507565563 (or 507565516 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 1121212121021 its reverse (1201212121211), we get a palindrome (2322424242232).

The spelling of 1121212121021 in words is "one trillion, one hundred twenty-one billion, two hundred twelve million, one hundred twenty-one thousand, twenty-one".