21024243311 has 4 divisors (see below), whose sum is σ = 21175497000. Its totient is φ = 20872989624.

The previous prime is 21024243277. The next prime is 21024243353. The reversal of 21024243311 is 11334242012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21024243311 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 (21024243011) 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, 75626636 + ... + 75626913.

It is an arithmetic number, because the mean of its divisors is an integer number (5293874250).

Almost surely, 2^21024243311 is an apocalyptic number.

21024243311 is a deficient number, since it is larger than the sum of its proper divisors (151253689).

21024243311 is a wasteful number, since it uses less digits than its factorization.

21024243311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151253688.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21024243311 its reverse (11334242012), we get a palindrome (32358485323).

The spelling of 21024243311 in words is "twenty-one billion, twenty-four million, two hundred forty-three thousand, three hundred eleven".