865156 has 6 divisors (see below), whose sum is σ = 1514030. Its totient is φ = 432576.

The previous prime is 865153. The next prime is 865159. The reversal of 865156 is 651568.

It is an interprime number because it is at equal distance from previous prime (865153) and next prime (865159).

It can be written as a sum of positive squares in only one way, i.e., 864900 + 256 = 930^2 + 16^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (865153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108141 + ... + 108148.

2⁸⁶⁵¹⁵⁶ is an apocalyptic number.

It is an amenable number.

865156 is a deficient number, since it is larger than the sum of its proper divisors (648874).

865156 is a wasteful number, since it uses less digits than its factorization.

865156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216293 (or 216291 counting only the distinct ones).

The product of its digits is 7200, while the sum is 31.

The square root of 865156 is about 930.1376242256. The cubic root of 865156 is about 95.2865218639.

Adding to 865156 its product of digits (7200), we get a square (872356 = 934²).

It can be divided in two parts, 865 and 156, that multiplied together give a triangular number (134940 = T₅₁₉).

The spelling of 865156 in words is "eight hundred sixty-five thousand, one hundred fifty-six".