75861 has 6 divisors (see below), whose sum is σ = 109590. Its totient is φ = 50568.

The previous prime is 75853. The next prime is 75869. The reversal of 75861 is 16857.

It is an interprime number because it is at equal distance from previous prime (75853) and next prime (75869).

It can be written as a sum of positive squares in only one way, i.e., 53361 + 22500 = 231^2 + 150^2 .

It is not a de Polignac number, because 75861 - 2³ = 75853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4206 + ... + 4223.

It is an arithmetic number, because the mean of its divisors is an integer number (18265).

2⁷⁵⁸⁶¹ is an apocalyptic number.

It is an amenable number.

75861 is a deficient number, since it is larger than the sum of its proper divisors (33729).

75861 is a wasteful number, since it uses less digits than its factorization.

75861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8435 (or 8432 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 75861 is about 275.4287566686. The cubic root of 75861 is about 42.3323964218.

The spelling of 75861 in words is "seventy-five thousand, eight hundred sixty-one".