21102028127 has 2 divisors, whose sum is σ = 21102028128. Its totient is φ = 21102028126.

The previous prime is 21102028111. The next prime is 21102028169. The reversal of 21102028127 is 72182020112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21102028127 - 2⁴ = 21102028111 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21102028096 and 21102028105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21102028187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10551014063 + 10551014064.

It is an arithmetic number, because the mean of its divisors is an integer number (10551014064).

Almost surely, 2^21102028127 is an apocalyptic number.

21102028127 is a deficient number, since it is larger than the sum of its proper divisors (1).

21102028127 is an equidigital number, since it uses as much as digits as its factorization.

21102028127 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 896, while the sum is 26.

Adding to 21102028127 its reverse (72182020112), we get a palindrome (93284048239).

The spelling of 21102028127 in words is "twenty-one billion, one hundred two million, twenty-eight thousand, one hundred twenty-seven".