21012101027 has 2 divisors, whose sum is σ = 21012101028. Its totient is φ = 21012101026.

The previous prime is 21012101009. The next prime is 21012101057. The reversal of 21012101027 is 72010121012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21012101027 - 2²⁸ = 20743665571 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21012100996 and 21012101014.

It is not a weakly prime, because it can be changed into another prime (21012101057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506050513 + 10506050514.

It is an arithmetic number, because the mean of its divisors is an integer number (10506050514).

Almost surely, 2^21012101027 is an apocalyptic number.

21012101027 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012101027 is an equidigital number, since it uses as much as digits as its factorization.

21012101027 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 56, while the sum is 17.

Adding to 21012101027 its reverse (72010121012), we get a palindrome (93022222039).

The spelling of 21012101027 in words is "twenty-one billion, twelve million, one hundred one thousand, twenty-seven".