815138426 has 12 divisors (see below), whose sum is σ = 1228134222. Its totient is φ = 405763056.

The previous prime is 815138411. The next prime is 815138497. The reversal of 815138426 is 624831518.

It can be written as a sum of positive squares in 3 ways, for example, as 133980625 + 681157801 = 11575^2 + 26099^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 815138426.

It is an unprimeable number.

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 5 ways as a sum of consecutive naturals, for example, 671396 + ... + 672608.

Almost surely, 2^815138426 is an apocalyptic number.

815138426 is a deficient number, since it is larger than the sum of its proper divisors (412995796).

815138426 is an equidigital number, since it uses as much as digits as its factorization.

815138426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2705 (or 1492 counting only the distinct ones).

The product of its digits is 46080, while the sum is 38.

The square root of 815138426 is about 28550.6291699500. The cubic root of 815138426 is about 934.1367444800.

The spelling of 815138426 in words is "eight hundred fifteen million, one hundred thirty-eight thousand, four hundred twenty-six".