261730144 has 48 divisors (see below), whose sum is σ = 557141760. Its totient is φ = 120314880.

The previous prime is 261730129. The next prime is 261730151. The reversal of 261730144 is 441037162.

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, 115777 + ... + 118015.

It is an arithmetic number, because the mean of its divisors is an integer number (11607120).

Almost surely, 2^261730144 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261730144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (278570880).

261730144 is an abundant number, since it is smaller than the sum of its proper divisors (295411616).

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

261730144 is a wasteful number, since it uses less digits than its factorization.

261730144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2543 (or 2535 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 261730144 is about 16178.0760289968. The cubic root of 261730144 is about 639.6630257317.

It can be divided in two parts, 2617 and 30144, that added together give a square (32761 = 181²).

The spelling of 261730144 in words is "two hundred sixty-one million, seven hundred thirty thousand, one hundred forty-four".