261043536 has 40 divisors (see below), whose sum is σ = 726238240. Its totient is φ = 80320896.

The previous prime is 261043511. The next prime is 261043579. The reversal of 261043536 is 635340162.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 208546 + ... + 209793.

It is an arithmetic number, because the mean of its divisors is an integer number (18155956).

Almost surely, 2^261043536 is an apocalyptic number.

261043536 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

261043536 is an abundant number, since it is smaller than the sum of its proper divisors (465194704).

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

261043536 is a wasteful number, since it uses less digits than its factorization.

261043536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418363 (or 418357 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 30.

The square root of 261043536 is about 16156.8417705937. The cubic root of 261043536 is about 639.1031840053.

Adding to 261043536 its reverse (635340162), we get a palindrome (896383698).

The spelling of 261043536 in words is "two hundred sixty-one million, forty-three thousand, five hundred thirty-six".