21713887889 has 8 divisors (see below), whose sum is σ = 21960230760. Its totient is φ = 21468160000.

The previous prime is 21713887883. The next prime is 21713887901. The reversal of 21713887889 is 98878831712.

It can be written as a sum of positive squares in 4 ways, for example, as 5313243664 + 16400644225 = 72892^2 + 128065^2 .

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 21713887889 - 2¹⁶ = 21713822353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21713887883) 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 7 ways as a sum of consecutive naturals, for example, 82544 + ... + 224145.

It is an arithmetic number, because the mean of its divisors is an integer number (2745028845).

Almost surely, 2^21713887889 is an apocalyptic number.

It is an amenable number.

21713887889 is a deficient number, since it is larger than the sum of its proper divisors (246342871).

21713887889 is a wasteful number, since it uses less digits than its factorization.

21713887889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307491.

The product of its digits is 10838016, while the sum is 62.

The spelling of 21713887889 in words is "twenty-one billion, seven hundred thirteen million, eight hundred eighty-seven thousand, eight hundred eighty-nine".