20812136 has 8 divisors (see below), whose sum is σ = 39022770. Its totient is φ = 10406064.

The previous prime is 20812123. The next prime is 20812139. The reversal of 20812136 is 63121802.

It can be written as a sum of positive squares in only one way, i.e., 18232900 + 2579236 = 4270^2 + 1606^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (20812139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1300751 + ... + 1300766.

Almost surely, 2^20812136 is an apocalyptic number.

It is an amenable number.

20812136 is a deficient number, since it is larger than the sum of its proper divisors (18210634).

20812136 is a wasteful number, since it uses less digits than its factorization.

20812136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2601523 (or 2601519 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 20812136 is about 4562.0320033950. The cubic root of 20812136 is about 275.0672496688.

Adding to 20812136 its reverse (63121802), we get a palindrome (83933938).

The spelling of 20812136 in words is "twenty million, eight hundred twelve thousand, one hundred thirty-six".