20853081 has 6 divisors (see below), whose sum is σ = 30121130. Its totient is φ = 13902048.

The previous prime is 20853061. The next prime is 20853083. The reversal of 20853081 is 18035802.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 20385225 + 467856 = 4515^2 + 684^2 .

It is not a de Polignac number, because 20853081 - 2⁹ = 20852569 is a prime.

It is a super-2 number, since 2×20853081² = 869701974385122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20853083) 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 5 ways as a sum of consecutive naturals, for example, 1158496 + ... + 1158513.

Almost surely, 2^20853081 is an apocalyptic number.

It is an amenable number.

20853081 is a deficient number, since it is larger than the sum of its proper divisors (9268049).

20853081 is a wasteful number, since it uses less digits than its factorization.

20853081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2317015 (or 2317012 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 20853081 is about 4566.5173819882. The cubic root of 20853081 is about 275.2475170973.

Adding to 20853081 its reverse (18035802), we get a palindrome (38888883).

The spelling of 20853081 in words is "twenty million, eight hundred fifty-three thousand, eighty-one".