21332171 has 16 divisors (see below), whose sum is σ = 25183488. Its totient is φ = 17690400.

The previous prime is 21332159. The next prime is 21332183. The reversal of 21332171 is 17123312.

It is an interprime number because it is at equal distance from previous prime (21332159) and next prime (21332183).

It is not a de Polignac number, because 21332171 - 2¹⁰ = 21331147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21332141) 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, 39161 + ... + 39701.

It is an arithmetic number, because the mean of its divisors is an integer number (1573968).

Almost surely, 2^21332171 is an apocalyptic number.

21332171 is a deficient number, since it is larger than the sum of its proper divisors (3851317).

21332171 is a wasteful number, since it uses less digits than its factorization.

21332171 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 722.

The product of its digits is 252, while the sum is 20.

The square root of 21332171 is about 4618.6763255288. The cubic root of 21332171 is about 277.3394726680.

Adding to 21332171 its reverse (17123312), we get a palindrome (38455483).

The spelling of 21332171 in words is "twenty-one million, three hundred thirty-two thousand, one hundred seventy-one".