861598 has 4 divisors (see below), whose sum is σ = 1292400. Its totient is φ = 430798.

The previous prime is 861589. The next prime is 861599. The reversal of 861598 is 895168.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×861598² = 1484702227208, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 215398 + ... + 215401.

It is an arithmetic number, because the mean of its divisors is an integer number (323100).

2⁸⁶¹⁵⁹⁸ is an apocalyptic number.

861598 is a deficient number, since it is larger than the sum of its proper divisors (430802).

861598 is a wasteful number, since it uses less digits than its factorization.

861598 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430801.

The product of its digits is 17280, while the sum is 37.

The square root of 861598 is about 928.2230335431. The cubic root of 861598 is about 95.1557187608.

Adding to 861598 its product of digits (17280), we get a palindrome (878878).

The spelling of 861598 in words is "eight hundred sixty-one thousand, five hundred ninety-eight".