21617016 has 32 divisors (see below), whose sum is σ = 54396240. Its totient is φ = 7158528.

The previous prime is 21616999. The next prime is 21617021. The reversal of 21617016 is 61071612.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 900 + ... + 6636.

Almost surely, 2^21617016 is an apocalyptic number.

It is an amenable number.

21617016 is an abundant number, since it is smaller than the sum of its proper divisors (32779224).

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

21617016 is a wasteful number, since it uses less digits than its factorization.

21617016 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5903 (or 5899 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 21617016 is about 4649.4102851867. The cubic root of 21617016 is about 278.5684416323.

Adding to 21617016 its reverse (61071612), we get a palindrome (82688628).

The spelling of 21617016 in words is "twenty-one million, six hundred seventeen thousand, sixteen".