813381861 has 8 divisors (see below), whose sum is σ = 1084659840. Its totient is φ = 542179232.

The previous prime is 813381827. The next prime is 813381883. The reversal of 813381861 is 168183318.

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 813381861 - 2¹⁴ = 813365477 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813381061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15076 + ... + 43058.

It is an arithmetic number, because the mean of its divisors is an integer number (135582480).

Almost surely, 2^813381861 is an apocalyptic number.

It is an amenable number.

813381861 is a deficient number, since it is larger than the sum of its proper divisors (271277979).

813381861 is a wasteful number, since it uses less digits than its factorization.

813381861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37675.

The product of its digits is 27648, while the sum is 39.

The square root of 813381861 is about 28519.8502976436. The cubic root of 813381861 is about 933.4652626289.

The spelling of 813381861 in words is "eight hundred thirteen million, three hundred eighty-one thousand, eight hundred sixty-one".