21124221289 has 8 divisors (see below), whose sum is σ = 21764625480. Its totient is φ = 20492774016.

The previous prime is 21124221271. The next prime is 21124221331. The reversal of 21124221289 is 98212242112.

It can be written as a sum of positive squares in 4 ways, for example, as 3665091600 + 17459129689 = 60540^2 + 132133^2 .

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 21124221289 - 2²¹ = 21122124137 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21124221689) 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, 2234442 + ... + 2243875.

It is an arithmetic number, because the mean of its divisors is an integer number (2720578185).

Almost surely, 2^21124221289 is an apocalyptic number.

It is an amenable number.

21124221289 is a deficient number, since it is larger than the sum of its proper divisors (640404191).

21124221289 is an equidigital number, since it uses as much as digits as its factorization.

21124221289 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4478459.

The product of its digits is 9216, while the sum is 34.

The spelling of 21124221289 in words is "twenty-one billion, one hundred twenty-four million, two hundred twenty-one thousand, two hundred eighty-nine".