817641243 has 12 divisors (see below), whose sum is σ = 1211540520. Its totient is φ = 544995108.

The previous prime is 817641241. The next prime is 817641257. The reversal of 817641243 is 342146718.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

817641243 is a `hidden beast` number, since 8 + 1 + 7 + 641 + 2 + 4 + 3 = 666.

It is not a de Polignac number, because 817641243 - 2¹ = 817641241 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 817641198 and 817641207.

It is not an unprimeable number, because it can be changed into a prime (817641241) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 145830 + ... + 151332.

It is an arithmetic number, because the mean of its divisors is an integer number (100961710).

Almost surely, 2^817641243 is an apocalyptic number.

817641243 is a deficient number, since it is larger than the sum of its proper divisors (393899277).

817641243 is an frugal number, since it uses more digits than its factorization.

817641243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11015 (or 5506 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 817641243 is about 28594.4267821546. The cubic root of 817641243 is about 935.0918315630.

The spelling of 817641243 in words is "eight hundred seventeen million, six hundred forty-one thousand, two hundred forty-three".