1221001033313 has 4 divisors (see below), whose sum is σ = 1221136513428. Its totient is φ = 1220865553200.

The previous prime is 1221001033271. The next prime is 1221001033319. The reversal of 1221001033313 is 3133301001221.

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 516260931169 + 704740102144 = 718513^2 + 839488^2 .

It is a cyclic number.

It is not a de Polignac number, because 1221001033313 - 2²⁸ = 1220732597857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221001033319) 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, 67726538 + ... + 67744563.

It is an arithmetic number, because the mean of its divisors is an integer number (305284128357).

Almost surely, 2^{1221001033313} is an apocalyptic number.

It is an amenable number.

1221001033313 is a deficient number, since it is larger than the sum of its proper divisors (135480115).

1221001033313 is an equidigital number, since it uses as much as digits as its factorization.

1221001033313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135480114.

The product of its (nonzero) digits is 324, while the sum is 20.

Adding to 1221001033313 its reverse (3133301001221), we get a palindrome (4354302034534).

The spelling of 1221001033313 in words is "one trillion, two hundred twenty-one billion, one million, thirty-three thousand, three hundred thirteen".