21586566489 has 4 divisors (see below), whose sum is σ = 28782088656. Its totient is φ = 14391044324.

The previous prime is 21586566473. The next prime is 21586566497. The reversal of 21586566489 is 98466568512.

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 21586566489 - 2⁴ = 21586566473 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21586562489) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3597761079 + ... + 3597761084.

It is an arithmetic number, because the mean of its divisors is an integer number (7195522164).

Almost surely, 2^21586566489 is an apocalyptic number.

It is an amenable number.

21586566489 is a deficient number, since it is larger than the sum of its proper divisors (7195522167).

21586566489 is an equidigital number, since it uses as much as digits as its factorization.

21586566489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7195522166.

The product of its digits is 24883200, while the sum is 60.

The spelling of 21586566489 in words is "twenty-one billion, five hundred eighty-six million, five hundred sixty-six thousand, four hundred eighty-nine".