1013321020021 has 4 divisors (see below), whose sum is σ = 1013476420044. Its totient is φ = 1013165620000.

The previous prime is 1013321020007. The next prime is 1013321020057. The reversal of 1013321020021 is 1200201233101.

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 890967975921 + 122353044100 = 943911^2 + 349790^2 .

It is a cyclic number.

It is not a de Polignac number, because 1013321020021 - 2³⁵ = 978961281653 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1013321019977 and 1013321020004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1013321020091) 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, 77690230 + ... + 77703271.

It is an arithmetic number, because the mean of its divisors is an integer number (253369105011).

Almost surely, 2^{1013321020021} is an apocalyptic number.

It is an amenable number.

1013321020021 is a deficient number, since it is larger than the sum of its proper divisors (155400023).

1013321020021 is an equidigital number, since it uses as much as digits as its factorization.

1013321020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155400022.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 1013321020021 its reverse (1200201233101), we get a palindrome (2213522253122).

The spelling of 1013321020021 in words is "one trillion, thirteen billion, three hundred twenty-one million, twenty thousand, twenty-one".