21434466689 has 4 divisors (see below), whose sum is σ = 22173586260. Its totient is φ = 20695347120.

The previous prime is 21434466593. The next prime is 21434466719. The reversal of 21434466689 is 98666443412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3798626689 + 17635840000 = 61633^2 + 132800^2 .

It is a cyclic number.

It is not a de Polignac number, because 21434466689 - 2¹² = 21434462593 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21434466689.

It is not an unprimeable number, because it can be changed into a prime (21434466589) 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, 369559742 + ... + 369559799.

It is an arithmetic number, because the mean of its divisors is an integer number (5543396565).

Almost surely, 2^21434466689 is an apocalyptic number.

21434466689 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

21434466689 is a deficient number, since it is larger than the sum of its proper divisors (739119571).

21434466689 is an equidigital number, since it uses as much as digits as its factorization.

21434466689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739119570.

The product of its digits is 5971968, while the sum is 53.

The spelling of 21434466689 in words is "twenty-one billion, four hundred thirty-four million, four hundred sixty-six thousand, six hundred eighty-nine".