21111200020987 has 2 divisors, whose sum is σ = 21111200020988. Its totient is φ = 21111200020986.

The previous prime is 21111200020979. The next prime is 21111200021033. The reversal of 21111200020987 is 78902000211112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21111200020987 - 2³ = 21111200020979 is a prime.

It is a super-2 number, since 2×21111200020987² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21111200020187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555600010493 + 10555600010494.

It is an arithmetic number, because the mean of its divisors is an integer number (10555600010494).

Almost surely, 2^{21111200020987} is an apocalyptic number.

21111200020987 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111200020987 is an equidigital number, since it uses as much as digits as its factorization.

21111200020987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 34.

The spelling of 21111200020987 in words is "twenty-one trillion, one hundred eleven billion, two hundred million, twenty thousand, nine hundred eighty-seven".