865038138 has 32 divisors (see below), whose sum is σ = 1773182400. Its totient is φ = 281183616.

The previous prime is 865038121. The next prime is 865038151. The reversal of 865038138 is 831830568.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 865038138.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 180558 + ... + 185286.

It is an arithmetic number, because the mean of its divisors is an integer number (55411950).

Almost surely, 2^865038138 is an apocalyptic number.

865038138 is an abundant number, since it is smaller than the sum of its proper divisors (908144262).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

865038138 is a wasteful number, since it uses less digits than its factorization.

865038138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5486.

The product of its (nonzero) digits is 138240, while the sum is 42.

The square root of 865038138 is about 29411.5306980103. The cubic root of 865038138 is about 952.8219464046.

The spelling of 865038138 in words is "eight hundred sixty-five million, thirty-eight thousand, one hundred thirty-eight".