815942 has 4 divisors (see below), whose sum is σ = 1223916. Its totient is φ = 407970.

The previous prime is 815939. The next prime is 815953. The reversal of 815942 is 249518.

815942 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 249518 = 2 ⋅124759.

It is a super-2 number, since 2×815942² = 1331522694728, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203984 + ... + 203987.

It is an arithmetic number, because the mean of its divisors is an integer number (305979).

2⁸¹⁵⁹⁴² is an apocalyptic number.

815942 is a deficient number, since it is larger than the sum of its proper divisors (407974).

815942 is a wasteful number, since it uses less digits than its factorization.

815942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407973.

The product of its digits is 2880, while the sum is 29.

The square root of 815942 is about 903.2950791408. The cubic root of 815942 is about 93.4443605027. Note that the first 3 decimals are identical.

The spelling of 815942 in words is "eight hundred fifteen thousand, nine hundred forty-two".