21011331133 has 4 divisors (see below), whose sum is σ = 22627587388. Its totient is φ = 19395074880.

The previous prime is 21011331023. The next prime is 21011331149. The reversal of 21011331133 is 33113311012.

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 7078361689 + 13932969444 = 84133^2 + 118038^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011331133 is a prime.

It is a super-4 number, since 4×21011331133⁴ (a number of 42 digits) contains 4444 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21011331133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011334133) 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, 808128108 + ... + 808128133.

It is an arithmetic number, because the mean of its divisors is an integer number (5656896847).

Almost surely, 2^21011331133 is an apocalyptic number.

It is an amenable number.

21011331133 is a deficient number, since it is larger than the sum of its proper divisors (1616256255).

21011331133 is a wasteful number, since it uses less digits than its factorization.

21011331133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1616256254.

The product of its (nonzero) digits is 162, while the sum is 19.

Adding to 21011331133 its reverse (33113311012), we get a palindrome (54124642145).

The spelling of 21011331133 in words is "twenty-one billion, eleven million, three hundred thirty-one thousand, one hundred thirty-three".