815138 has 12 divisors (see below), whose sum is σ = 1291590. Its totient is φ = 385776.

The previous prime is 815123. The next prime is 815141. The reversal of 815138 is 831518.

It can be written as a sum of positive squares in only one way, i.e., 797449 + 17689 = 893^2 + 133^2 .

It is a nialpdrome in base 7.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 158 + ... + 1286.

2⁸¹⁵¹³⁸ is an apocalyptic number.

815138 is a deficient number, since it is larger than the sum of its proper divisors (476452).

815138 is a wasteful number, since it uses less digits than its factorization.

815138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1169 (or 1150 counting only the distinct ones).

The product of its digits is 960, while the sum is 26.

The square root of 815138 is about 902.8499321593. The cubic root of 815138 is about 93.4136581750.

It can be divided in two parts, 8 and 15138, that multiplied together give a square (121104 = 348²).

The spelling of 815138 in words is "eight hundred fifteen thousand, one hundred thirty-eight".