256060721 has 6 divisors (see below), whose sum is σ = 297866610. Its totient is φ = 219480576.

The previous prime is 256060639. The next prime is 256060723. The reversal of 256060721 is 127060652.

256060721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 247621696 + 8439025 = 15736^2 + 2905^2 .

It is not a de Polignac number, because 256060721 - 2¹⁰ = 256059697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256060723) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2612816 + ... + 2612913.

It is an arithmetic number, because the mean of its divisors is an integer number (49644435).

Almost surely, 2^256060721 is an apocalyptic number.

It is an amenable number.

256060721 is a deficient number, since it is larger than the sum of its proper divisors (41805889).

256060721 is an equidigital number, since it uses as much as digits as its factorization.

256060721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5225743 (or 5225736 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 256060721 is about 16001.8974187438. The cubic root of 256060721 is about 635.0106192037.

The spelling of 256060721 in words is "two hundred fifty-six million, sixty thousand, seven hundred twenty-one".