1256660525 has 6 divisors (see below), whose sum is σ = 1558259082. Its totient is φ = 1005328400.

The previous prime is 1256660521. The next prime is 1256660597. The reversal of 1256660525 is 5250666521.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 454276 + 1256206249 = 674^2 + 35443^2 .

It is not a de Polignac number, because 1256660525 - 2² = 1256660521 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1256660521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 25133186 + ... + 25133235.

It is an arithmetic number, because the mean of its divisors is an integer number (259709847).

Almost surely, 2^1256660525 is an apocalyptic number.

It is an amenable number.

1256660525 is a deficient number, since it is larger than the sum of its proper divisors (301598557).

1256660525 is an equidigital number, since it uses as much as digits as its factorization.

1256660525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50266431 (or 50266426 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 1256660525 is about 35449.4079640267. The cubic root of 1256660525 is about 1079.1272455864.

The spelling of 1256660525 in words is "one billion, two hundred fifty-six million, six hundred sixty thousand, five hundred twenty-five".