1221102211121 has 4 divisors (see below), whose sum is σ = 1315033150452. Its totient is φ = 1127171271792.

The previous prime is 1221102211103. The next prime is 1221102211129. The reversal of 1221102211121 is 1211122011221.

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 357949727521 + 863152483600 = 598289^2 + 929060^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221102211121 - 2²⁶ = 1221035102257 is a prime.

It is a super-2 number, since 2×1221102211121² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221102211121.

It is not an unprimeable number, because it can be changed into a prime (1221102211129) 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, 46965469646 + ... + 46965469671.

It is an arithmetic number, because the mean of its divisors is an integer number (328758287613).

Almost surely, 2^{1221102211121} is an apocalyptic number.

It is an amenable number.

1221102211121 is a deficient number, since it is larger than the sum of its proper divisors (93930939331).

1221102211121 is an equidigital number, since it uses as much as digits as its factorization.

1221102211121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93930939330.

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

Adding to 1221102211121 its reverse (1211122011221), we get a palindrome (2432224222342).

The spelling of 1221102211121 in words is "one trillion, two hundred twenty-one billion, one hundred two million, two hundred eleven thousand, one hundred twenty-one".