815842385 has 16 divisors (see below), whose sum is σ = 985645584. Its totient is φ = 648268032.

The previous prime is 815842381. The next prime is 815842399. The reversal of 815842385 is 583248518.

It can be written as a sum of positive squares in 8 ways, for example, as 146119744 + 669722641 = 12088^2 + 25879^2 .

It is not a de Polignac number, because 815842385 - 2² = 815842381 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (815842381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 545699 + ... + 547191.

It is an arithmetic number, because the mean of its divisors is an integer number (61602849).

Almost surely, 2^815842385 is an apocalyptic number.

It is an amenable number.

815842385 is a deficient number, since it is larger than the sum of its proper divisors (169803199).

815842385 is a wasteful number, since it uses less digits than its factorization.

815842385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2164.

The product of its digits is 307200, while the sum is 44.

The square root of 815842385 is about 28562.9547666203. The cubic root of 815842385 is about 934.4055760213.

The spelling of 815842385 in words is "eight hundred fifteen million, eight hundred forty-two thousand, three hundred eighty-five".