261963 has 12 divisors (see below), whose sum is σ = 407680. Its totient is φ = 161136.

The previous prime is 261959. The next prime is 261971. The reversal of 261963 is 369162.

It is a happy number.

It is not a de Polignac number, because 261963 - 2² = 261959 is a prime.

It is a super-2 number, since 2×261963² = 137249226738, which contains 22 as substring.

It is a fibodiv number, since the Fibonacci-like sequence with seeds 261 and 963 contains 261963 itself.

It is not an unprimeable number, because it can be changed into a prime (261973) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1003 + ... + 1236.

2²⁶¹⁹⁶³ is an apocalyptic number.

261963 is a deficient number, since it is larger than the sum of its proper divisors (145717).

261963 is a wasteful number, since it uses less digits than its factorization.

261963 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2258 (or 2255 counting only the distinct ones).

The product of its digits is 1944, while the sum is 27.

The square root of 261963 is about 511.8232116659. The cubic root of 261963 is about 63.9852667909.

The spelling of 261963 in words is "two hundred sixty-one thousand, nine hundred sixty-three".