21223404431 has 8 divisors (see below), whose sum is σ = 21497985600. Its totient is φ = 20948971680.

The previous prime is 21223404413. The next prime is 21223404437. The reversal of 21223404431 is 13440432212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21223404431 - 2³⁴ = 4043535247 is a prime.

It is a super-2 number, since 2×21223404431² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21223404431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223404437) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 266705 + ... + 337013.

It is an arithmetic number, because the mean of its divisors is an integer number (2687248200).

Almost surely, 2^21223404431 is an apocalyptic number.

21223404431 is a deficient number, since it is larger than the sum of its proper divisors (274581169).

21223404431 is an equidigital number, since it uses as much as digits as its factorization.

21223404431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74209.

The product of its (nonzero) digits is 4608, while the sum is 26.

Adding to 21223404431 its reverse (13440432212), we get a palindrome (34663836643).

The spelling of 21223404431 in words is "twenty-one billion, two hundred twenty-three million, four hundred four thousand, four hundred thirty-one".