813438281 has 4 divisors (see below), whose sum is σ = 813874452. Its totient is φ = 813002112.

The previous prime is 813438271. The next prime is 813438293. The reversal of 813438281 is 182834318.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 182834318 = 2 ⋅91417159.

It can be written as a sum of positive squares in 2 ways, for example, as 468073225 + 345365056 = 21635^2 + 18584^2 .

It is a cyclic number.

It is not a de Polignac number, because 813438281 - 2¹⁴ = 813421897 is a prime.

It is a super-2 number, since 2×813438281² = 1323363673992469922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (813438221) 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 3 ways as a sum of consecutive naturals, for example, 215276 + ... + 219021.

It is an arithmetic number, because the mean of its divisors is an integer number (203468613).

Almost surely, 2^813438281 is an apocalyptic number.

It is an amenable number.

813438281 is a deficient number, since it is larger than the sum of its proper divisors (436171).

813438281 is a wasteful number, since it uses less digits than its factorization.

813438281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436170.

The product of its digits is 36864, while the sum is 38.

The square root of 813438281 is about 28520.8394161182. The cubic root of 813438281 is about 933.4868453135.

The spelling of 813438281 in words is "eight hundred thirteen million, four hundred thirty-eight thousand, two hundred eighty-one".