21127271 has 16 divisors (see below), whose sum is σ = 24295680. Its totient is φ = 18184320.

The previous prime is 21127247. The next prime is 21127273. The reversal of 21127271 is 17272112.

It is not a de Polignac number, because 21127271 - 2¹⁸ = 20865127 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21127273) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28220 + ... + 28958.

It is an arithmetic number, because the mean of its divisors is an integer number (1518480).

Almost surely, 2^21127271 is an apocalyptic number.

21127271 is a deficient number, since it is larger than the sum of its proper divisors (3168409).

21127271 is a wasteful number, since it uses less digits than its factorization.

21127271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 886.

The product of its digits is 392, while the sum is 23.

The square root of 21127271 is about 4596.4411233040. The cubic root of 21127271 is about 276.4486463232.

Adding to 21127271 its reverse (17272112), we get a palindrome (38399383).

The spelling of 21127271 in words is "twenty-one million, one hundred twenty-seven thousand, two hundred seventy-one".