256961777 has 2 divisors, whose sum is σ = 256961778. Its totient is φ = 256961776.

The previous prime is 256961753. The next prime is 256961791. The reversal of 256961777 is 777169652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 232745536 + 24216241 = 15256^2 + 4921^2 .

It is a cyclic number.

It is not a de Polignac number, because 256961777 - 2⁶ = 256961713 is a prime.

It is not a weakly prime, because it can be changed into another prime (256961797) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128480888 + 128480889.

It is an arithmetic number, because the mean of its divisors is an integer number (128480889).

Almost surely, 2^256961777 is an apocalyptic number.

It is an amenable number.

256961777 is a deficient number, since it is larger than the sum of its proper divisors (1).

256961777 is an equidigital number, since it uses as much as digits as its factorization.

256961777 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1111320, while the sum is 50.

The square root of 256961777 is about 16030.0273549361. The cubic root of 256961777 is about 635.7545967573.

It can be divided in two parts, 2569 and 61777, that added together give a palindrome (64346).

The spelling of 256961777 in words is "two hundred fifty-six million, nine hundred sixty-one thousand, seven hundred seventy-seven".