261416320 has 128 divisors (see below), whose sum is σ = 692686080. Its totient is φ = 93542400.

The previous prime is 261416317. The next prime is 261416357. The reversal of 261416320 is 23614162.

It is a tau number, because it is divible by the number of its divisors (128).

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 15 ways as a sum of consecutive naturals, for example, 499579 + ... + 500101.

It is an arithmetic number, because the mean of its divisors is an integer number (5411610).

Almost surely, 2^261416320 is an apocalyptic number.

261416320 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 261416320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (346343040).

261416320 is an abundant number, since it is smaller than the sum of its proper divisors (431269760).

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

261416320 is a wasteful number, since it uses less digits than its factorization.

261416320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624 (or 612 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 261416320 is about 16168.3740679142. The cubic root of 261416320 is about 639.4072637065.

The spelling of 261416320 in words is "two hundred sixty-one million, four hundred sixteen thousand, three hundred twenty".