20800817 has 8 divisors (see below), whose sum is σ = 21660072. Its totient is φ = 19958400.

The previous prime is 20800807. The next prime is 20800841. The reversal of 20800817 is 71800802.

It can be written as a sum of positive squares in 4 ways, for example, as 379456 + 20421361 = 616^2 + 4519^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 20800817 - 2⁸ = 20800561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20800807) 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 7 ways as a sum of consecutive naturals, for example, 1658 + ... + 6659.

It is an arithmetic number, because the mean of its divisors is an integer number (2707509).

Almost surely, 2^20800817 is an apocalyptic number.

It is an amenable number.

20800817 is a deficient number, since it is larger than the sum of its proper divisors (859255).

20800817 is an equidigital number, since it uses as much as digits as its factorization.

20800817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8419.

The product of its (nonzero) digits is 896, while the sum is 26.

The square root of 20800817 is about 4560.7912690672. The cubic root of 20800817 is about 275.0173741089.

The spelling of 20800817 in words is "twenty million, eight hundred thousand, eight hundred seventeen".