21888673871 has 2 divisors, whose sum is σ = 21888673872. Its totient is φ = 21888673870.

The previous prime is 21888673847. The next prime is 21888673889. The reversal of 21888673871 is 17837688812.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21888673871 is a prime.

It is a super-2 number, since 2×21888673871² (a number of 21 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21888673871.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21888673811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10944336935 + 10944336936.

It is an arithmetic number, because the mean of its divisors is an integer number (10944336936).

Almost surely, 2^21888673871 is an apocalyptic number.

21888673871 is a deficient number, since it is larger than the sum of its proper divisors (1).

21888673871 is an equidigital number, since it uses as much as digits as its factorization.

21888673871 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7225344, while the sum is 59.

The spelling of 21888673871 in words is "twenty-one billion, eight hundred eighty-eight million, six hundred seventy-three thousand, eight hundred seventy-one".