261540224 has 32 divisors (see below), whose sum is σ = 568407240. Its totient is φ = 118881280.

The previous prime is 261540217. The next prime is 261540259. The reversal of 261540224 is 422045162.

It is a tau number, because it is divible by the number of its divisors (32).

It is a junction number, because it is equal to n+sod(n) for n = 261540193 and 261540202.

It is a congruent number.

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, 91469 + ... + 94284.

Almost surely, 2^261540224 is an apocalyptic number.

It is an amenable number.

261540224 is an abundant number, since it is smaller than the sum of its proper divisors (306867016).

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

261540224 is a wasteful number, since it uses less digits than its factorization.

261540224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185778 (or 185766 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The square root of 261540224 is about 16172.2052917962. The cubic root of 261540224 is about 639.5082681172.

Adding to 261540224 its reverse (422045162), we get a palindrome (683585386).

The spelling of 261540224 in words is "two hundred sixty-one million, five hundred forty thousand, two hundred twenty-four".