645542526032857 has 2 divisors, whose sum is σ = 645542526032858. Its totient is φ = 645542526032856.

The previous prime is 645542526032779. The next prime is 645542526032867. The reversal of 645542526032857 is 758230625245546.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 442946701597401 + 202595824435456 = 21046299^2 + 14233616^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645542526032857 is a prime.

It is not a weakly prime, because it can be changed into another prime (645542526032867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322771263016428 + 322771263016429.

It is an arithmetic number, because the mean of its divisors is an integer number (322771263016429).

Almost surely, 2^{645542526032857} is an apocalyptic number.

It is an amenable number.

645542526032857 is a deficient number, since it is larger than the sum of its proper divisors (1).

645542526032857 is an equidigital number, since it uses as much as digits as its factorization.

645542526032857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 483840000, while the sum is 64.

The spelling of 645542526032857 in words is "six hundred forty-five trillion, five hundred forty-two billion, five hundred twenty-six million, thirty-two thousand, eight hundred fifty-seven".