261356 has 12 divisors (see below), whose sum is σ = 460992. Its totient is φ = 129648.

The previous prime is 261353. The next prime is 261379. The reversal of 261356 is 653162.

It is a hoax number, since the sum of its digits (23) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (261353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 746 + ... + 1038.

It is an arithmetic number, because the mean of its divisors is an integer number (38416).

2²⁶¹³⁵⁶ is an apocalyptic number.

It is an amenable number.

261356 is a deficient number, since it is larger than the sum of its proper divisors (199636).

261356 is a wasteful number, since it uses less digits than its factorization.

261356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 520 (or 518 counting only the distinct ones).

The product of its digits is 1080, while the sum is 23.

The square root of 261356 is about 511.2298895800. The cubic root of 261356 is about 63.9358080328.

The spelling of 261356 in words is "two hundred sixty-one thousand, three hundred fifty-six".