21044650859 has 4 divisors (see below), whose sum is σ = 21047461704. Its totient is φ = 21041840016.

The previous prime is 21044650841. The next prime is 21044650873. The reversal of 21044650859 is 95805644012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21044650859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21044652859) 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, 1394162 + ... + 1409175.

It is an arithmetic number, because the mean of its divisors is an integer number (5261865426).

Almost surely, 2^21044650859 is an apocalyptic number.

21044650859 is a deficient number, since it is larger than the sum of its proper divisors (2810845).

21044650859 is an equidigital number, since it uses as much as digits as its factorization.

21044650859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2810844.

The product of its (nonzero) digits is 345600, while the sum is 44.

The spelling of 21044650859 in words is "twenty-one billion, forty-four million, six hundred fifty thousand, eight hundred fifty-nine".