256421611 has 8 divisors (see below), whose sum is σ = 263914560. Its totient is φ = 249033672.

The previous prime is 256421609. The next prime is 256421621. The reversal of 256421611 is 116124652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256421611 - 2¹ = 256421609 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256421611.

It is not an unprimeable number, because it can be changed into a prime (256421621) 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 7 ways as a sum of consecutive naturals, for example, 21285 + ... + 31078.

It is an arithmetic number, because the mean of its divisors is an integer number (32989320).

Almost surely, 2^256421611 is an apocalyptic number.

256421611 is a deficient number, since it is larger than the sum of its proper divisors (7492949).

256421611 is an equidigital number, since it uses as much as digits as its factorization.

256421611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52505.

The product of its digits is 2880, while the sum is 28.

The square root of 256421611 is about 16013.1699235348. The cubic root of 256421611 is about 635.3088055123.

The spelling of 256421611 in words is "two hundred fifty-six million, four hundred twenty-one thousand, six hundred eleven".