261441240 has 32 divisors (see below), whose sum is σ = 784324080. Its totient is φ = 69717632.

The previous prime is 261441239. The next prime is 261441269. The reversal of 261441240 is 42144162.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 261441240.

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, 1089219 + ... + 1089458.

Almost surely, 2^261441240 is an apocalyptic number.

261441240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261441240 is an abundant number, since it is smaller than the sum of its proper divisors (522882840).

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

261441240 is a wasteful number, since it uses less digits than its factorization.

261441240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2178691 (or 2178687 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

The square root of 261441240 is about 16169.1446898097. The cubic root of 261441240 is about 639.4275806256.

The spelling of 261441240 in words is "two hundred sixty-one million, four hundred forty-one thousand, two hundred forty".