261282320 has 40 divisors (see below), whose sum is σ = 654213336. Its totient is φ = 96473088.

The previous prime is 261282313. The next prime is 261282341. The reversal of 261282320 is 23282162.

It can be written as a sum of positive squares in 4 ways, for example, as 4129024 + 257153296 = 2032^2 + 16036^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (26).

It is a self number, because there is not a number n which added to its sum of digits gives 261282320.

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 7 ways as a sum of consecutive naturals, for example, 124577 + ... + 126656.

Almost surely, 2^261282320 is an apocalyptic number.

261282320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261282320 is an abundant number, since it is smaller than the sum of its proper divisors (392931016).

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

261282320 is a wasteful number, since it uses less digits than its factorization.

261282320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 251259 (or 251253 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 261282320 is about 16164.2296444959. The cubic root of 261282320 is about 639.2979932814.

The spelling of 261282320 in words is "two hundred sixty-one million, two hundred eighty-two thousand, three hundred twenty".