21712182887 has 2 divisors, whose sum is σ = 21712182888. Its totient is φ = 21712182886.

The previous prime is 21712182847. The next prime is 21712182977. The reversal of 21712182887 is 78828121712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21712182887 - 2⁸ = 21712182631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21712182847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10856091443 + 10856091444.

It is an arithmetic number, because the mean of its divisors is an integer number (10856091444).

Almost surely, 2^21712182887 is an apocalyptic number.

21712182887 is a deficient number, since it is larger than the sum of its proper divisors (1).

21712182887 is an equidigital number, since it uses as much as digits as its factorization.

21712182887 is an evil number, because the sum of its binary digits is even.

The product of its digits is 200704, while the sum is 47.

The spelling of 21712182887 in words is "twenty-one billion, seven hundred twelve million, one hundred eighty-two thousand, eight hundred eighty-seven".