21517134 has 8 divisors (see below), whose sum is σ = 43034280. Its totient is φ = 7172376.

The previous prime is 21517127. The next prime is 21517163. The reversal of 21517134 is 43171512.

It is a sphenic number, since it is the product of 3 distinct primes.

21517134 is an admirable number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 1793089 + ... + 1793100.

It is an arithmetic number, because the mean of its divisors is an integer number (5379285).

Almost surely, 2^21517134 is an apocalyptic number.

21517134 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21517134 is a wasteful number, since it uses less digits than its factorization.

21517134 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3586194.

The product of its digits is 840, while the sum is 24.

The square root of 21517134 is about 4638.6564865271. The cubic root of 21517134 is about 278.1387348181.

Adding to 21517134 its reverse (43171512), we get a palindrome (64688646).

The spelling of 21517134 in words is "twenty-one million, five hundred seventeen thousand, one hundred thirty-four".