815803385 has 8 divisors (see below), whose sum is σ = 979396296. Its totient is φ = 652354560.

The previous prime is 815803367. The next prime is 815803403. The reversal of 815803385 is 583308518.

It is an interprime number because it is at equal distance from previous prime (815803367) and next prime (815803403).

It can be written as a sum of positive squares in 4 ways, for example, as 410143504 + 405659881 = 20252^2 + 20141^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 815803385 - 2¹⁴ = 815787001 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23144 + ... + 46553.

It is an arithmetic number, because the mean of its divisors is an integer number (122424537).

Almost surely, 2^815803385 is an apocalyptic number.

It is an amenable number.

815803385 is a deficient number, since it is larger than the sum of its proper divisors (163592911).

815803385 is a wasteful number, since it uses less digits than its factorization.

815803385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72043.

The product of its (nonzero) digits is 115200, while the sum is 41.

The square root of 815803385 is about 28562.2720559832. The cubic root of 815803385 is about 934.3906865448.

The spelling of 815803385 in words is "eight hundred fifteen million, eight hundred three thousand, three hundred eighty-five".