256840725 has 48 divisors (see below), whose sum is σ = 434972160. Its totient is φ = 133694400.

The previous prime is 256840723. The next prime is 256840729. The reversal of 256840725 is 527048652.

256840725 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 256840725 - 2¹ = 256840723 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256840723) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 740002 + ... + 740348.

It is an arithmetic number, because the mean of its divisors is an integer number (9061920).

Almost surely, 2^256840725 is an apocalyptic number.

256840725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

256840725 is a deficient number, since it is larger than the sum of its proper divisors (178131435).

256840725 is a wasteful number, since it uses less digits than its factorization.

256840725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 570 (or 565 counting only the distinct ones).

The product of its (nonzero) digits is 134400, while the sum is 39.

The square root of 256840725 is about 16026.2511212074. The cubic root of 256840725 is about 635.6547486340.

The spelling of 256840725 in words is "two hundred fifty-six million, eight hundred forty thousand, seven hundred twenty-five".