1221121201113 has 144 divisors (see below), whose sum is σ = 2071807225488. Its totient is φ = 690127257600.

The previous prime is 1221121201103. The next prime is 1221121201117. The reversal of 1221121201113 is 3111021211221.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 10709766144 + 1210411434969 = 103488^2 + 1100187^2 .

It is not a de Polignac number, because 1221121201113 - 2²⁶ = 1221054092249 is a prime.

It is a super-2 number, since 2×1221121201113² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221121201117) by changing a digit.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1249867681 + ... + 1249868657.

It is an arithmetic number, because the mean of its divisors is an integer number (14387550177).

Almost surely, 2^{1221121201113} is an apocalyptic number.

It is an amenable number.

1221121201113 is a deficient number, since it is larger than the sum of its proper divisors (850686024375).

1221121201113 is a wasteful number, since it uses less digits than its factorization.

1221121201113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1576 (or 1562 counting only the distinct ones).

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

Adding to 1221121201113 its reverse (3111021211221), we get a palindrome (4332142412334).

The spelling of 1221121201113 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred one thousand, one hundred thirteen".