21707468891 has 8 divisors (see below), whose sum is σ = 22068653904. Its totient is φ = 21347377920.

The previous prime is 21707468879. The next prime is 21707468917. The reversal of 21707468891 is 19886470712.

It is a happy number.

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 21707468891 - 2¹⁰ = 21707467867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21707468801) 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 7 ways as a sum of consecutive naturals, for example, 233450 + ... + 312911.

It is an arithmetic number, because the mean of its divisors is an integer number (2758581738).

Almost surely, 2^21707468891 is an apocalyptic number.

21707468891 is a deficient number, since it is larger than the sum of its proper divisors (361185013).

21707468891 is an equidigital number, since it uses as much as digits as its factorization.

21707468891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 547021.

The product of its (nonzero) digits is 1354752, while the sum is 53.

The spelling of 21707468891 in words is "twenty-one billion, seven hundred seven million, four hundred sixty-eight thousand, eight hundred ninety-one".