865138547 has 24 divisors (see below), whose sum is σ = 1073281824. Its totient is φ = 682815744.

The previous prime is 865138531. The next prime is 865138567. The reversal of 865138547 is 745831568.

It is not a de Polignac number, because 865138547 - 2⁴ = 865138531 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (865138507) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 724583 + ... + 725775.

It is an arithmetic number, because the mean of its divisors is an integer number (44720076).

Almost surely, 2^865138547 is an apocalyptic number.

865138547 is a deficient number, since it is larger than the sum of its proper divisors (208143277).

865138547 is a wasteful number, since it uses less digits than its factorization.

865138547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1839 (or 1826 counting only the distinct ones).

The product of its digits is 806400, while the sum is 47.

The square root of 865138547 is about 29413.2376150603. The cubic root of 865138547 is about 952.8588111366.

The spelling of 865138547 in words is "eight hundred sixty-five million, one hundred thirty-eight thousand, five hundred forty-seven".