21002240323 has 4 divisors (see below), whose sum is σ = 21004582648. Its totient is φ = 20999898000.

The previous prime is 21002240321. The next prime is 21002240339. The reversal of 21002240323 is 32304220012.

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 21002240323 - 2¹ = 21002240321 is a prime.

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 21002240323.

It is not an unprimeable number, because it can be changed into a prime (21002240321) 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, 1157661 + ... + 1175662.

It is an arithmetic number, because the mean of its divisors is an integer number (5251145662).

Almost surely, 2^21002240323 is an apocalyptic number.

21002240323 is a deficient number, since it is larger than the sum of its proper divisors (2342325).

21002240323 is an equidigital number, since it uses as much as digits as its factorization.

21002240323 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2342324.

The product of its (nonzero) digits is 576, while the sum is 19.

Adding to 21002240323 its reverse (32304220012), we get a palindrome (53306460335).

The spelling of 21002240323 in words is "twenty-one billion, two million, two hundred forty thousand, three hundred twenty-three".