261156 has 24 divisors (see below), whose sum is σ = 696640. Its totient is φ = 74592.

The previous prime is 261127. The next prime is 261167. The reversal of 261156 is 651162.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 261156.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1471 + ... + 1638.

2²⁶¹¹⁵⁶ is an apocalyptic number.

It is an amenable number.

261156 is an abundant number, since it is smaller than the sum of its proper divisors (435484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261156 is a wasteful number, since it uses less digits than its factorization.

261156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3123 (or 3121 counting only the distinct ones).

The product of its digits is 360, while the sum is 21.

The square root of 261156 is about 511.0342454278. The cubic root of 261156 is about 63.9194951305.

The spelling of 261156 in words is "two hundred sixty-one thousand, one hundred fifty-six".