21116271 has 16 divisors (see below), whose sum is σ = 31465728. Its totient is φ = 12484800.

The previous prime is 21116267. The next prime is 21116273. The reversal of 21116271 is 17261112.

It is a happy number.

It is not a de Polignac number, because 21116271 - 2² = 21116267 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21116273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6451 + ... + 9156.

It is an arithmetic number, because the mean of its divisors is an integer number (1966608).

Almost surely, 2^21116271 is an apocalyptic number.

21116271 is a deficient number, since it is larger than the sum of its proper divisors (10349457).

21116271 is a wasteful number, since it uses less digits than its factorization.

21116271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15662.

The product of its digits is 168, while the sum is 21.

The square root of 21116271 is about 4595.2443895836. The cubic root of 21116271 is about 276.4006599549.

Adding to 21116271 its reverse (17261112), we get a palindrome (38377383).

The spelling of 21116271 in words is "twenty-one million, one hundred sixteen thousand, two hundred seventy-one".