21043342311 has 4 divisors (see below), whose sum is σ = 28057789752. Its totient is φ = 14028894872.

The previous prime is 21043342303. The next prime is 21043342337. The reversal of 21043342311 is 11324334012.

It is a happy number.

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 21043342311 - 2³ = 21043342303 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21043342301) 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, 3507223716 + ... + 3507223721.

It is an arithmetic number, because the mean of its divisors is an integer number (7014447438).

Almost surely, 2^21043342311 is an apocalyptic number.

21043342311 is a deficient number, since it is larger than the sum of its proper divisors (7014447441).

21043342311 is an equidigital number, since it uses as much as digits as its factorization.

21043342311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7014447440.

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21043342311 its reverse (11324334012), we get a palindrome (32367676323).

The spelling of 21043342311 in words is "twenty-one billion, forty-three million, three hundred forty-two thousand, three hundred eleven".