21043113311 has 4 divisors (see below), whose sum is σ = 22956123624. Its totient is φ = 19130103000.

The previous prime is 21043113293. The next prime is 21043113367. The reversal of 21043113311 is 11331134012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21043113311 - 2³⁴ = 3863244127 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21043110311) 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, 956505140 + ... + 956505161.

It is an arithmetic number, because the mean of its divisors is an integer number (5739030906).

Almost surely, 2^21043113311 is an apocalyptic number.

21043113311 is a deficient number, since it is larger than the sum of its proper divisors (1913010313).

21043113311 is a wasteful number, since it uses less digits than its factorization.

21043113311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1913010312.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 21043113311 its reverse (11331134012), we get a palindrome (32374247323).

The spelling of 21043113311 in words is "twenty-one billion, forty-three million, one hundred thirteen thousand, three hundred eleven".