809193953893 has 4 divisors (see below), whose sum is σ = 871439642668. Its totient is φ = 746948265120.

The previous prime is 809193953861. The next prime is 809193953923. The reversal of 809193953893 is 398359391908.

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

It can be written as a sum of positive squares in 2 ways, for example, as 60288909444 + 748905044449 = 245538^2 + 865393^2 .

It is a cyclic number.

It is not a de Polignac number, because 809193953893 - 2⁵ = 809193953861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (809193953803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31122844368 + ... + 31122844393.

It is an arithmetic number, because the mean of its divisors is an integer number (217859910667).

Almost surely, 2^809193953893 is an apocalyptic number.

It is an amenable number.

809193953893 is a deficient number, since it is larger than the sum of its proper divisors (62245688775).

809193953893 is a wasteful number, since it uses less digits than its factorization.

809193953893 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62245688774.

The product of its (nonzero) digits is 56687040, while the sum is 67.

The spelling of 809193953893 in words is "eight hundred nine billion, one hundred ninety-three million, nine hundred fifty-three thousand, eight hundred ninety-three".