1256032681 has 2 divisors, whose sum is σ = 1256032682. Its totient is φ = 1256032680.

The previous prime is 1256032669. The next prime is 1256032721. The reversal of 1256032681 is 1862306521.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1219127056 + 36905625 = 34916^2 + 6075^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1256032681 is a prime.

It is a super-2 number, since 2×1256032681² = 3155236191480095522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1256032621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 628016340 + 628016341.

It is an arithmetic number, because the mean of its divisors is an integer number (628016341).

Almost surely, 2^1256032681 is an apocalyptic number.

It is an amenable number.

1256032681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1256032681 is an equidigital number, since it uses as much as digits as its factorization.

1256032681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 1256032681 is about 35440.5513642212. The cubic root of 1256032681 is about 1078.9475002965.

The spelling of 1256032681 in words is "one billion, two hundred fifty-six million, thirty-two thousand, six hundred eighty-one".