21243423632 has 20 divisors (see below), whose sum is σ = 43325404080. Its totient is φ = 10062674208.

The previous prime is 21243423623. The next prime is 21243423647. The reversal of 21243423632 is 23632434212.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34939538 + ... + 34940145.

It is an arithmetic number, because the mean of its divisors is an integer number (2166270204).

Almost surely, 2^21243423632 is an apocalyptic number.

It is an amenable number.

21243423632 is an abundant number, since it is smaller than the sum of its proper divisors (22081980448).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21243423632 is a wasteful number, since it uses less digits than its factorization.

21243423632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69879710 (or 69879704 counting only the distinct ones).

The product of its digits is 41472, while the sum is 32.

Adding to 21243423632 its reverse (23632434212), we get a palindrome (44875857844).

The spelling of 21243423632 in words is "twenty-one billion, two hundred forty-three million, four hundred twenty-three thousand, six hundred thirty-two".