13511020021 has 4 divisors (see below), whose sum is σ = 13511260672. Its totient is φ = 13510779372.

The previous prime is 13511020013. The next prime is 13511020043. The reversal of 13511020021 is 12002011531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 13511020021 - 2³ = 13511020013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13511019977 and 13511020004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13511020051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13516 + ... + 164938.

It is an arithmetic number, because the mean of its divisors is an integer number (3377815168).

Almost surely, 2^13511020021 is an apocalyptic number.

It is an amenable number.

13511020021 is a deficient number, since it is larger than the sum of its proper divisors (240651).

13511020021 is an equidigital number, since it uses as much as digits as its factorization.

13511020021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240650.

The product of its (nonzero) digits is 60, while the sum is 16.

Adding to 13511020021 its reverse (12002011531), we get a palindrome (25513031552).

The spelling of 13511020021 in words is "thirteen billion, five hundred eleven million, twenty thousand, twenty-one".