21104224399 has 4 divisors (see below), whose sum is σ = 21371366560. Its totient is φ = 20837082240.

The previous prime is 21104224363. The next prime is 21104224441. The reversal of 21104224399 is 99342240112.

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 21104224399 - 2⁹ = 21104223887 is a prime.

It is a super-2 number, since 2×21104224399² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21104228399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133570962 + ... + 133571119.

It is an arithmetic number, because the mean of its divisors is an integer number (5342841640).

Almost surely, 2^21104224399 is an apocalyptic number.

21104224399 is a deficient number, since it is larger than the sum of its proper divisors (267142161).

21104224399 is an equidigital number, since it uses as much as digits as its factorization.

21104224399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 267142160.

The product of its (nonzero) digits is 31104, while the sum is 37.

The spelling of 21104224399 in words is "twenty-one billion, one hundred four million, two hundred twenty-four thousand, three hundred ninety-nine".