21016017 has 40 divisors (see below), whose sum is σ = 34731840. Its totient is φ = 12558240.

The previous prime is 21016013. The next prime is 21016027. The reversal of 21016017 is 71061012.

It is not a de Polignac number, because 21016017 - 2² = 21016013 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21016013) 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 39 ways as a sum of consecutive naturals, for example, 91659 + ... + 91887.

It is an arithmetic number, because the mean of its divisors is an integer number (868296).

Almost surely, 2^21016017 is an apocalyptic number.

21016017 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21016017 is a deficient number, since it is larger than the sum of its proper divisors (13715823).

21016017 is a wasteful number, since it uses less digits than its factorization.

21016017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355 (or 346 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 18.

The square root of 21016017 is about 4584.3229598273. The cubic root of 21016017 is about 275.9625421756.

Adding to 21016017 its reverse (71061012), we get a palindrome (92077029).

It can be divided in two parts, 2101 and 6017, that added together give a palindrome (8118).

The spelling of 21016017 in words is "twenty-one million, sixteen thousand, seventeen".