21012201271 has 2 divisors, whose sum is σ = 21012201272. Its totient is φ = 21012201270.

The previous prime is 21012201211. The next prime is 21012201281. The reversal of 21012201271 is 17210221012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21012201271 - 2¹⁵ = 21012168503 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21012201211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506100635 + 10506100636.

It is an arithmetic number, because the mean of its divisors is an integer number (10506100636).

Almost surely, 2^21012201271 is an apocalyptic number.

21012201271 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012201271 is an equidigital number, since it uses as much as digits as its factorization.

21012201271 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 112, while the sum is 19.

Adding to 21012201271 its reverse (17210221012), we get a palindrome (38222422283).

The spelling of 21012201271 in words is "twenty-one billion, twelve million, two hundred one thousand, two hundred seventy-one".