21246171 has 16 divisors (see below), whose sum is σ = 29272320. Its totient is φ = 13698720.

The previous prime is 21246167. The next prime is 21246179. The reversal of 21246171 is 17164212.

It is not a de Polignac number, because 21246171 - 2² = 21246167 is a prime.

It is a super-2 number, since 2×21246171² = 902799564322482, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21246179) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13306 + ... + 14816.

It is an arithmetic number, because the mean of its divisors is an integer number (1829520).

Almost surely, 2^21246171 is an apocalyptic number.

21246171 is a deficient number, since it is larger than the sum of its proper divisors (8026149).

21246171 is a wasteful number, since it uses less digits than its factorization.

21246171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1666.

The product of its digits is 672, while the sum is 24.

The square root of 21246171 is about 4609.3568965746. The cubic root of 21246171 is about 276.9662754843.

The spelling of 21246171 in words is "twenty-one million, two hundred forty-six thousand, one hundred seventy-one".