20810986 has 24 divisors (see below), whose sum is σ = 36823140. Its totient is φ = 8793792.

The previous prime is 20810981. The next prime is 20810987. The reversal of 20810986 is 68901802.

It can be written as a sum of positive squares in 2 ways, for example, as 19633761 + 1177225 = 4431^2 + 1085^2 .

It is not an unprimeable number, because it can be changed into a prime (20810981) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5700 + ... + 8608.

Almost surely, 2^20810986 is an apocalyptic number.

20810986 is a deficient number, since it is larger than the sum of its proper divisors (16012154).

20810986 is a wasteful number, since it uses less digits than its factorization.

20810986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2998 (or 2991 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 20810986 is about 4561.9059613280. The cubic root of 20810986 is about 275.0621831832.

The spelling of 20810986 in words is "twenty million, eight hundred ten thousand, nine hundred eighty-six".