21112100009887 has 2 divisors, whose sum is σ = 21112100009888. Its totient is φ = 21112100009886.

The previous prime is 21112100009839. The next prime is 21112100010007. The reversal of 21112100009887 is 78890000121112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21112100009887 - 2³¹ = 21109952526239 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21112100003887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556050004943 + 10556050004944.

It is an arithmetic number, because the mean of its divisors is an integer number (10556050004944).

Almost surely, 2^{21112100009887} is an apocalyptic number.

21112100009887 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112100009887 is an equidigital number, since it uses as much as digits as its factorization.

21112100009887 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 40.

The spelling of 21112100009887 in words is "twenty-one trillion, one hundred twelve billion, one hundred million, nine thousand, eight hundred eighty-seven".