20445516 has 108 divisors (see below), whose sum is σ = 64423632. Its totient is φ = 5323968.

The previous prime is 20445499. The next prime is 20445521. The reversal of 20445516 is 61554402.

20445516 is a `hidden beast` number, since 204 + 455 + 1 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 20445516.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 258765 + ... + 258843.

Almost surely, 2^20445516 is an apocalyptic number.

20445516 is a gapful number since it is divisible by the number (26) 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 20445516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32211816).

20445516 is an abundant number, since it is smaller than the sum of its proper divisors (43978116).

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

20445516 is a wasteful number, since it uses less digits than its factorization.

20445516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 188 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 27.

The square root of 20445516 is about 4521.6718147163. The cubic root of 20445516 is about 273.4425057979.

Adding to 20445516 its reverse (61554402), we get a palindrome (81999918).

The spelling of 20445516 in words is "twenty million, four hundred forty-five thousand, five hundred sixteen".