261214240 has 144 divisors (see below), whose sum is σ = 728142912. Its totient is φ = 86727168.

The previous prime is 261214229. The next prime is 261214271. The reversal of 261214240 is 42412162.

It is a happy number.

It is an unprimeable 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 23 ways as a sum of consecutive naturals, for example, 3898687 + ... + 3898753.

It is an arithmetic number, because the mean of its divisors is an integer number (5056548).

Almost surely, 2^261214240 is an apocalyptic number.

261214240 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 261214240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (364071456).

261214240 is an abundant number, since it is smaller than the sum of its proper divisors (466928672).

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

261214240 is an equidigital number, since it uses as much as digits as its factorization.

261214240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207 (or 140 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 261214240 is about 16162.1236228412. The cubic root of 261214240 is about 639.2424630691.

The spelling of 261214240 in words is "two hundred sixty-one million, two hundred fourteen thousand, two hundred forty".