861257839 has 8 divisors (see below), whose sum is σ = 967835232. Its totient is φ = 760441440.

The previous prime is 861257819. The next prime is 861257851. The reversal of 861257839 is 938752168.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 861257839 - 2²³ = 852869231 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 861257792 and 861257801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861257809) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1439932 + ... + 1440529.

It is an arithmetic number, because the mean of its divisors is an integer number (120979404).

Almost surely, 2^861257839 is an apocalyptic number.

861257839 is a deficient number, since it is larger than the sum of its proper divisors (106577393).

861257839 is a wasteful number, since it uses less digits than its factorization.

861257839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2880497.

The product of its digits is 725760, while the sum is 49.

The square root of 861257839 is about 29347.1947381688. The cubic root of 861257839 is about 951.4319454223.

The spelling of 861257839 in words is "eight hundred sixty-one million, two hundred fifty-seven thousand, eight hundred thirty-nine".