20812786 has 4 divisors (see below), whose sum is σ = 31219182. Its totient is φ = 10406392.

The previous prime is 20812751. The next prime is 20812793. The reversal of 20812786 is 68721802.

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

It can be written as a sum of positive squares in only one way, i.e., 13549761 + 7263025 = 3681^2 + 2695^2 .

It is a super-2 number, since 2×20812786² = 866344122163592, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5203195 + ... + 5203198.

Almost surely, 2^20812786 is an apocalyptic number.

20812786 is a deficient number, since it is larger than the sum of its proper divisors (10406396).

20812786 is a wasteful number, since it uses less digits than its factorization.

20812786 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10406395.

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 20812786 is about 4562.1032430229. The cubic root of 20812786 is about 275.0701132521.

The spelling of 20812786 in words is "twenty million, eight hundred twelve thousand, seven hundred eighty-six".