645253626352441 has 2 divisors, whose sum is σ = 645253626352442. Its totient is φ = 645253626352440.

The previous prime is 645253626352421. The next prime is 645253626352483. The reversal of 645253626352441 is 144253626352546.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 508251774913600 + 137001851438841 = 22544440^2 + 11704779^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645253626352441 is a prime.

It is not a weakly prime, because it can be changed into another prime (645253626352411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322626813176220 + 322626813176221.

It is an arithmetic number, because the mean of its divisors is an integer number (322626813176221).

Almost surely, 2^{645253626352441} is an apocalyptic number.

It is an amenable number.

645253626352441 is a deficient number, since it is larger than the sum of its proper divisors (1).

645253626352441 is an equidigital number, since it uses as much as digits as its factorization.

645253626352441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 124416000, while the sum is 58.

The spelling of 645253626352441 in words is "six hundred forty-five trillion, two hundred fifty-three billion, six hundred twenty-six million, three hundred fifty-two thousand, four hundred forty-one".