1221020101121 has 4 divisors (see below), whose sum is σ = 1221646588500. Its totient is φ = 1220393613744.

The previous prime is 1221020101117. The next prime is 1221020101129. The reversal of 1221020101121 is 1211010201221.

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 1071823313521 + 149196787600 = 1035289^2 + 386260^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221020101121 - 2² = 1221020101117 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221020101096 and 1221020101105.

It is not an unprimeable number, because it can be changed into a prime (1221020101129) 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, 313240766 + ... + 313244663.

It is an arithmetic number, because the mean of its divisors is an integer number (305411647125).

Almost surely, 2^{1221020101121} is an apocalyptic number.

It is an amenable number.

1221020101121 is a deficient number, since it is larger than the sum of its proper divisors (626487379).

1221020101121 is an equidigital number, since it uses as much as digits as its factorization.

1221020101121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626487378.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1221020101121 its reverse (1211010201221), we get a palindrome (2432030302342).

The spelling of 1221020101121 in words is "one trillion, two hundred twenty-one billion, twenty million, one hundred one thousand, one hundred twenty-one".