21100219087 has 2 divisors, whose sum is σ = 21100219088. Its totient is φ = 21100219086.

The previous prime is 21100219079. The next prime is 21100219097. The reversal of 21100219087 is 78091200112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21100219087 - 2³ = 21100219079 is a prime.

It is a super-2 number, since 2×21100219087² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21100219027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10550109543 + 10550109544.

It is an arithmetic number, because the mean of its divisors is an integer number (10550109544).

Almost surely, 2^21100219087 is an apocalyptic number.

21100219087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21100219087 is an equidigital number, since it uses as much as digits as its factorization.

21100219087 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 31.

Adding to 21100219087 its reverse (78091200112), we get a palindrome (99191419199).

The spelling of 21100219087 in words is "twenty-one billion, one hundred million, two hundred nineteen thousand, eighty-seven".