256177609 has 2 divisors, whose sum is σ = 256177610. Its totient is φ = 256177608.

The previous prime is 256177549. The next prime is 256177631. The reversal of 256177609 is 906771652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 150601984 + 105575625 = 12272^2 + 10275^2 .

It is a cyclic number.

It is not a de Polignac number, because 256177609 - 2¹⁵ = 256144841 is a prime.

It is not a weakly prime, because it can be changed into another prime (256177639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128088804 + 128088805.

It is an arithmetic number, because the mean of its divisors is an integer number (128088805).

Almost surely, 2^256177609 is an apocalyptic number.

It is an amenable number.

256177609 is a deficient number, since it is larger than the sum of its proper divisors (1).

256177609 is an equidigital number, since it uses as much as digits as its factorization.

256177609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 158760, while the sum is 43.

The square root of 256177609 is about 16005.5493189081. The cubic root of 256177609 is about 635.1072288797.

The spelling of 256177609 in words is "two hundred fifty-six million, one hundred seventy-seven thousand, six hundred nine".