261998 has 8 divisors (see below), whose sum is σ = 428760. Its totient is φ = 119080.

The previous prime is 261983. The next prime is 262007. The reversal of 261998 is 899162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5933 + ... + 5976.

It is an arithmetic number, because the mean of its divisors is an integer number (53595).

2²⁶¹⁹⁹⁸ is an apocalyptic number.

261998 is a deficient number, since it is larger than the sum of its proper divisors (166762).

261998 is a wasteful number, since it uses less digits than its factorization.

261998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11922.

The product of its digits is 7776, while the sum is 35.

The square root of 261998 is about 511.8574020174. The cubic root of 261998 is about 63.9881162831.

The spelling of 261998 in words is "two hundred sixty-one thousand, nine hundred ninety-eight".