20011986 has 24 divisors (see below), whose sum is σ = 43531020. Its totient is φ = 6644256.

The previous prime is 20011967. The next prime is 20011987. The reversal of 20011986 is 68911002.

It can be written as a sum of positive squares in 2 ways, for example, as 19633761 + 378225 = 4431^2 + 615^2 .

It is not an unprimeable number, because it can be changed into a prime (20011987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2776 + ... + 6908.

Almost surely, 2^20011986 is an apocalyptic number.

20011986 is an abundant number, since it is smaller than the sum of its proper divisors (23519034).

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

20011986 is a wasteful number, since it uses less digits than its factorization.

20011986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4410 (or 4407 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 20011986 is about 4473.4758298218. The cubic root of 20011986 is about 271.4959758467.

Adding to 20011986 its reverse (68911002), we get a palindrome (88922988).

The spelling of 20011986 in words is "twenty million, eleven thousand, nine hundred eighty-six".