261964 has 12 divisors (see below), whose sum is σ = 464800. Its totient is φ = 129168.

The previous prime is 261959. The next prime is 261971. The reversal of 261964 is 469162.

It is an unprimeable number.

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, 99 + ... + 730.

261964 is a Friedman number, since it can be written as 6^2*(1-6)+4^9, using all its digits and the basic arithmetic operations.

2²⁶¹⁹⁶⁴ is an apocalyptic number.

It is an amenable number.

261964 is a deficient number, since it is larger than the sum of its proper divisors (202836).

261964 is a wasteful number, since it uses less digits than its factorization.

261964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 912 (or 910 counting only the distinct ones).

The product of its digits is 2592, while the sum is 28.

The square root of 261964 is about 511.8241885648. The cubic root of 261964 is about 63.9853482085.

It can be divided in two parts, 261 and 964, that added together give a triangular number (1225 = T₄₉).

The spelling of 261964 in words is "two hundred sixty-one thousand, nine hundred sixty-four".