21102443004431 has 4 divisors (see below), whose sum is σ = 21102454691472. Its totient is φ = 21102431317392.

The previous prime is 21102443004361. The next prime is 21102443004443. The reversal of 21102443004431 is 13440034420112.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21102443004431 - 2¹⁴ = 21102442988047 is a prime.

It is a super-2 number, since 2×21102443004431² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21102443004394 and 21102443004403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102443054431) 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, 2495771 + ... + 6959436.

It is an arithmetic number, because the mean of its divisors is an integer number (5275613672868).

Almost surely, 2^{21102443004431} is an apocalyptic number.

21102443004431 is a deficient number, since it is larger than the sum of its proper divisors (11687041).

21102443004431 is an equidigital number, since it uses as much as digits as its factorization.

21102443004431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11687040.

The product of its (nonzero) digits is 9216, while the sum is 29.

Adding to 21102443004431 its reverse (13440034420112), we get a palindrome (34542477424543).

The spelling of 21102443004431 in words is "twenty-one trillion, one hundred two billion, four hundred forty-three million, four thousand, four hundred thirty-one".