20416 has 28 divisors (see below), whose sum is σ = 45720. Its totient is φ = 8960.

The previous prime is 20411. The next prime is 20431. The reversal of 20416 is 61402.

It is a plaindrome in base 7.

It is a nialpdrome in base 12.

It is a zygodrome in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 20396 and 20405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 690 + ... + 718.

2²⁰⁴¹⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22860).

20416 is an abundant number, since it is smaller than the sum of its proper divisors (25304).

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

20416 is a wasteful number, since it uses less digits than its factorization.

20416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52 (or 42 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 20416 is about 142.8845687959. The cubic root of 20416 is about 27.3310858090.

Adding to 20416 its reverse (61402), we get a palindrome (81818).

It can be divided in two parts, 2041 and 6, that multiplied together give a triangular number (12246 = T₁₅₆).

The spelling of 20416 in words is "twenty thousand, four hundred sixteen".