16217680 has 40 divisors (see below), whose sum is σ = 38236392. Its totient is φ = 6395904.

The previous prime is 16217651. The next prime is 16217683. The reversal of 16217680 is 8671261.

It can be written as a sum of positive squares in 4 ways, for example, as 440896 + 15776784 = 664^2 + 3972^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a plaindrome in base 14.

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16217683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4452 + ... + 7228.

Almost surely, 2^16217680 is an apocalyptic number.

16217680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16217680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19118196).

16217680 is an abundant number, since it is smaller than the sum of its proper divisors (22018712).

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

16217680 is a wasteful number, since it uses less digits than its factorization.

16217680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2863 (or 2857 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 16217680 is about 4027.1180762426. The cubic root of 16217680 is about 253.1218148255.

The spelling of 16217680 in words is "sixteen million, two hundred seventeen thousand, six hundred eighty".