261037728 has 120 divisors (see below), whose sum is σ = 877437792. Its totient is φ = 74577024.

The previous prime is 261037723. The next prime is 261037747. The reversal of 261037728 is 827730162.

261037728 is a `hidden beast` number, since 2 + 610 + 37 + 7 + 2 + 8 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 261037692 and 261037701.

It is not an unprimeable number, because it can be changed into a prime (261037723) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 10951 + ... + 25337.

Almost surely, 2^261037728 is an apocalyptic number.

261037728 is a gapful number since it is divisible by the number (28) 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 261037728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (438718896).

261037728 is an abundant number, since it is smaller than the sum of its proper divisors (616400064).

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

261037728 is a wasteful number, since it uses less digits than its factorization.

261037728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14416 (or 14399 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 36.

The square root of 261037728 is about 16156.6620314965. The cubic root of 261037728 is about 639.0984441334.

The spelling of 261037728 in words is "two hundred sixty-one million, thirty-seven thousand, seven hundred twenty-eight".