256726505 has 16 divisors (see below), whose sum is σ = 355716480. Its totient is φ = 174223872.

The previous prime is 256726493. The next prime is 256726507. The reversal of 256726505 is 505627652.

It is a cyclic number.

It is not a de Polignac number, because 256726505 - 2¹² = 256722409 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (256726507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34415 + ... + 41204.

It is an arithmetic number, because the mean of its divisors is an integer number (22232280).

Almost surely, 2^256726505 is an apocalyptic number.

It is an amenable number.

256726505 is a deficient number, since it is larger than the sum of its proper divisors (98989975).

256726505 is an equidigital number, since it uses as much as digits as its factorization.

256726505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75728.

The product of its (nonzero) digits is 126000, while the sum is 38.

The square root of 256726505 is about 16022.6871965972. The cubic root of 256726505 is about 635.5605070235.

The spelling of 256726505 in words is "two hundred fifty-six million, seven hundred twenty-six thousand, five hundred five".