21017416 has 16 divisors (see below), whose sum is σ = 45037440. Its totient is φ = 9007440.

The previous prime is 21017407. The next prime is 21017419. The reversal of 21017416 is 61471012.

It is not an unprimeable number, because it can be changed into a prime (21017419) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 187600 + ... + 187711.

It is an arithmetic number, because the mean of its divisors is an integer number (2814840).

Almost surely, 2^21017416 is an apocalyptic number.

It is an amenable number.

21017416 is an abundant number, since it is smaller than the sum of its proper divisors (24020024).

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

21017416 is a wasteful number, since it uses less digits than its factorization.

21017416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 375324 (or 375320 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 21017416 is about 4584.4755425239. The cubic root of 21017416 is about 275.9686654898.

Adding to 21017416 its reverse (61471012), we get a palindrome (82488428).

The spelling of 21017416 in words is "twenty-one million, seventeen thousand, four hundred sixteen".