259920 has 90 divisors (see below), whose sum is σ = 921258. Its totient is φ = 65664.

The previous prime is 259907. The next prime is 259933. The reversal of 259920 is 29952.

It is an interprime number because it is at equal distance from previous prime (259907) and next prime (259933).

It can be written as a sum of positive squares in only one way, i.e., 207936 + 51984 = 456^2 + 228^2 .

It is a tau number, because it is divible by the number of its divisors (90).

It is a congruent number.

It is an unprimeable number.

259920 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 13671 + ... + 13689.

2²⁵⁹⁹²⁰ is an apocalyptic number.

259920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 259920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (460629).

259920 is an abundant number, since it is smaller than the sum of its proper divisors (661338).

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

259920 is a wasteful number, since it uses less digits than its factorization.

259920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57 (or 29 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 259920 is about 509.8234988700. The cubic root of 259920 is about 63.8184961588.

Multiplying 259920 by its product of nonzero digits (1620), we get a square (421070400 = 20520²).

The spelling of 259920 in words is "two hundred fifty-nine thousand, nine hundred twenty".