256057221 has 8 divisors (see below), whose sum is σ = 390182464. Its totient is φ = 146318400.

The previous prime is 256057187. The next prime is 256057223. The reversal of 256057221 is 122750652.

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

It is not a de Polignac number, because 256057221 - 2⁶ = 256057157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256057223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6096580 + ... + 6096621.

It is an arithmetic number, because the mean of its divisors is an integer number (48772808).

Almost surely, 2^256057221 is an apocalyptic number.

256057221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

256057221 is a deficient number, since it is larger than the sum of its proper divisors (134125243).

256057221 is a wasteful number, since it uses less digits than its factorization.

256057221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12193211.

The product of its (nonzero) digits is 8400, while the sum is 30.

The square root of 256057221 is about 16001.7880563392. The cubic root of 256057221 is about 635.0077259481.

The spelling of 256057221 in words is "two hundred fifty-six million, fifty-seven thousand, two hundred twenty-one".