21122410209 has 4 divisors (see below), whose sum is σ = 28163213616. Its totient is φ = 14081606804.

The previous prime is 21122410147. The next prime is 21122410229. The reversal of 21122410209 is 90201422112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21122410209 - 2⁷ = 21122410081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21122410229) 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, 3520401699 + ... + 3520401704.

It is an arithmetic number, because the mean of its divisors is an integer number (7040803404).

Almost surely, 2^21122410209 is an apocalyptic number.

It is an amenable number.

21122410209 is a deficient number, since it is larger than the sum of its proper divisors (7040803407).

21122410209 is an equidigital number, since it uses as much as digits as its factorization.

21122410209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7040803406.

The product of its (nonzero) digits is 576, while the sum is 24.

The spelling of 21122410209 in words is "twenty-one billion, one hundred twenty-two million, four hundred ten thousand, two hundred nine".