21234301243 has 4 divisors (see below), whose sum is σ = 21234700728. Its totient is φ = 21233901760.

The previous prime is 21234301241. The next prime is 21234301259. The reversal of 21234301243 is 34210343212.

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 21234301243 - 2¹ = 21234301241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21234301241) 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, 105046 + ... + 231307.

It is an arithmetic number, because the mean of its divisors is an integer number (5308675182).

Almost surely, 2^21234301243 is an apocalyptic number.

21234301243 is a deficient number, since it is larger than the sum of its proper divisors (399485).

21234301243 is an equidigital number, since it uses as much as digits as its factorization.

21234301243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399484.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21234301243 its reverse (34210343212), we get a palindrome (55444644455).

The spelling of 21234301243 in words is "twenty-one billion, two hundred thirty-four million, three hundred one thousand, two hundred forty-three".