256205506 has 8 divisors (see below), whose sum is σ = 385177104. Its totient is φ = 127813140.

The previous prime is 256205503. The next prime is 256205513. The reversal of 256205506 is 605502652.

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

It is a super-2 number, since 2×256205506² = 131282522609432072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (256205503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 143700 + ... + 145471.

It is an arithmetic number, because the mean of its divisors is an integer number (48147138).

Almost surely, 2^256205506 is an apocalyptic number.

256205506 is a deficient number, since it is larger than the sum of its proper divisors (128971598).

256205506 is a wasteful number, since it uses less digits than its factorization.

256205506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 289616.

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 256205506 is about 16006.4207741768. The cubic root of 256205506 is about 635.1302818224.

The spelling of 256205506 in words is "two hundred fifty-six million, two hundred five thousand, five hundred six".