20219985 has 12 divisors (see below), whose sum is σ = 35048052. Its totient is φ = 10783968.

The previous prime is 20219951. The next prime is 20220007. The reversal of 20219985 is 58991202.

It can be written as a sum of positive squares in 2 ways, for example, as 8503056 + 11716929 = 2916^2 + 3423^2 .

It is not a de Polignac number, because 20219985 - 2⁹ = 20219473 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 224622 + ... + 224711.

It is an arithmetic number, because the mean of its divisors is an integer number (2920671).

Almost surely, 2^20219985 is an apocalyptic number.

It is an amenable number.

20219985 is a deficient number, since it is larger than the sum of its proper divisors (14828067).

20219985 is a wasteful number, since it uses less digits than its factorization.

20219985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 449344 (or 449341 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 20219985 is about 4496.6637632805. The cubic root of 20219985 is about 272.4333535074.

The spelling of 20219985 in words is "twenty million, two hundred nineteen thousand, nine hundred eighty-five".