843199591081 has 3 divisors (see below), whose sum is σ = 843200509341. Its totient is φ = 843198672822.

The previous prime is 843199591067. The next prime is 843199591097. The reversal of 843199591081 is 180195991348.

The square root of 843199591081 is 918259.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 843199591081 - 2⁵ = 843199591049 is a prime.

It is a super-2 number, since 2×843199591081² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (843199591001) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 459130 + ... + 1377388.

It is an arithmetic number, because the mean of its divisors is an integer number (281066836447).

Almost surely, 2^843199591081 is an apocalyptic number.

843199591081 is the 918259-th square number.

843199591081 is the 459130-th centered octagonal number.

It is an amenable number.

843199591081 is a deficient number, since it is larger than the sum of its proper divisors (918260).

843199591081 is an frugal number, since it uses more digits than its factorization.

843199591081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1836518 (or 918259 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 58.

The spelling of 843199591081 in words is "eight hundred forty-three billion, one hundred ninety-nine million, five hundred ninety-one thousand, eighty-one".