21012432323 has 4 divisors (see below), whose sum is σ = 21012755208. Its totient is φ = 21012109440.

The previous prime is 21012432317. The next prime is 21012432373. The reversal of 21012432323 is 32323421012.

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 21012432323 - 2²⁰ = 21011383747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012432313) 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, 25886 + ... + 206627.

It is an arithmetic number, because the mean of its divisors is an integer number (5253188802).

Almost surely, 2^21012432323 is an apocalyptic number.

21012432323 is a deficient number, since it is larger than the sum of its proper divisors (322885).

21012432323 is an equidigital number, since it uses as much as digits as its factorization.

21012432323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322884.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 21012432323 its reverse (32323421012), we get a palindrome (53335853335).

The spelling of 21012432323 in words is "twenty-one billion, twelve million, four hundred thirty-two thousand, three hundred twenty-three".