815742939 has 16 divisors (see below), whose sum is σ = 1199871360. Its totient is φ = 488832960.

The previous prime is 815742923. The next prime is 815742973. The reversal of 815742939 is 939247518.

It is not a de Polignac number, because 815742939 - 2⁴ = 815742923 is a prime.

It is not an unprimeable number, because it can be changed into a prime (815742839) 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, 135937 + ... + 141810.

It is an arithmetic number, because the mean of its divisors is an integer number (74991960).

Almost surely, 2^815742939 is an apocalyptic number.

815742939 is a gapful number since it is divisible by the number (89) formed by its first and last digit.

815742939 is a deficient number, since it is larger than the sum of its proper divisors (384128421).

815742939 is a wasteful number, since it uses less digits than its factorization.

815742939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 277850.

The product of its digits is 544320, while the sum is 48.

The square root of 815742939 is about 28561.2138922701. The cubic root of 815742939 is about 934.3676084455.

The spelling of 815742939 in words is "eight hundred fifteen million, seven hundred forty-two thousand, nine hundred thirty-nine".