256566730 has 16 divisors (see below), whose sum is σ = 527794560. Its totient is φ = 87965712.

The previous prime is 256566677. The next prime is 256566733. The reversal of 256566730 is 37665652.

It is not an unprimeable number, because it can be changed into a prime (256566733) 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, 1832550 + ... + 1832689.

It is an arithmetic number, because the mean of its divisors is an integer number (32987160).

Almost surely, 2^256566730 is an apocalyptic number.

256566730 is an abundant number, since it is smaller than the sum of its proper divisors (271227830).

256566730 is a wasteful number, since it uses less digits than its factorization.

256566730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3665253.

The product of its (nonzero) digits is 226800, while the sum is 40.

The square root of 256566730 is about 16017.7005216105. The cubic root of 256566730 is about 635.4286315953.

The spelling of 256566730 in words is "two hundred fifty-six million, five hundred sixty-six thousand, seven hundred thirty".