21417832 has 16 divisors (see below), whose sum is σ = 40817700. Its totient is φ = 10533120.

The previous prime is 21417829. The next prime is 21417839. The reversal of 21417832 is 23871412.

It can be written as a sum of positive squares in 2 ways, for example, as 21399876 + 17956 = 4626^2 + 134^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21417832.

It is not an unprimeable number, because it can be changed into a prime (21417839) 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 3 ways as a sum of consecutive naturals, for example, 21457 + ... + 22432.

Almost surely, 2^21417832 is an apocalyptic number.

It is an amenable number.

21417832 is a deficient number, since it is larger than the sum of its proper divisors (19399868).

21417832 is a wasteful number, since it uses less digits than its factorization.

21417832 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43956 (or 43952 counting only the distinct ones).

The product of its digits is 2688, while the sum is 28.

The square root of 21417832 is about 4627.9403626235. The cubic root of 21417832 is about 277.7102029877.

The spelling of 21417832 in words is "twenty-one million, four hundred seventeen thousand, eight hundred thirty-two".