256722077 has 2 divisors, whose sum is σ = 256722078. Its totient is φ = 256722076.

The previous prime is 256722073. The next prime is 256722079. The reversal of 256722077 is 770227652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 224220676 + 32501401 = 14974^2 + 5701^2 .

It is a cyclic number.

It is not a de Polignac number, because 256722077 - 2² = 256722073 is a prime.

Together with 256722079, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256722077.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256722073) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128361038 + 128361039.

It is an arithmetic number, because the mean of its divisors is an integer number (128361039).

Almost surely, 2^256722077 is an apocalyptic number.

It is an amenable number.

256722077 is a deficient number, since it is larger than the sum of its proper divisors (1).

256722077 is an equidigital number, since it uses as much as digits as its factorization.

256722077 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 82320, while the sum is 38.

The square root of 256722077 is about 16022.5490169324. The cubic root of 256722077 is about 635.5568529687.

The spelling of 256722077 in words is "two hundred fifty-six million, seven hundred twenty-two thousand, seventy-seven".