20802785 has 8 divisors (see below), whose sum is σ = 25572456. Its totient is φ = 16236160.

The previous prime is 20802779. The next prime is 20802809. The reversal of 20802785 is 58720802.

It can be written as a sum of positive squares in 4 ways, for example, as 64 + 20802721 = 8^2 + 4561^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20802785 - 2¹² = 20798689 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 50534 + ... + 50943.

It is an arithmetic number, because the mean of its divisors is an integer number (3196557).

Almost surely, 2^20802785 is an apocalyptic number.

It is an amenable number.

20802785 is a deficient number, since it is larger than the sum of its proper divisors (4769671).

20802785 is a wasteful number, since it uses less digits than its factorization.

20802785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101523.

The product of its (nonzero) digits is 8960, while the sum is 32.

The square root of 20802785 is about 4561.0070159999. The cubic root of 20802785 is about 275.0260471196.

The spelling of 20802785 in words is "twenty million, eight hundred two thousand, seven hundred eighty-five".