20016985 has 4 divisors (see below), whose sum is σ = 24020388. Its totient is φ = 16013584.

The previous prime is 20016977. The next prime is 20017001. The reversal of 20016985 is 58961002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15303744 + 4713241 = 3912^2 + 2171^2 .

It is a cyclic number.

It is not a de Polignac number, because 20016985 - 2³ = 20016977 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2001694 + ... + 2001703.

It is an arithmetic number, because the mean of its divisors is an integer number (6005097).

Almost surely, 2^20016985 is an apocalyptic number.

It is an amenable number.

20016985 is a deficient number, since it is larger than the sum of its proper divisors (4003403).

20016985 is an equidigital number, since it uses as much as digits as its factorization.

20016985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4003402.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 20016985 is about 4474.0345327232. The cubic root of 20016985 is about 271.5185805561.

Adding to 20016985 its reverse (58961002), we get a palindrome (78977987).

The spelling of 20016985 in words is "twenty million, sixteen thousand, nine hundred eighty-five".