17645047699421 has 2 divisors, whose sum is σ = 17645047699422. Its totient is φ = 17645047699420.

The previous prime is 17645047699381. The next prime is 17645047699463. The reversal of 17645047699421 is 12499674054671.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14905738032025 + 2739309667396 = 3860795^2 + 1655086^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-17645047699421 is a prime.

It is a super-3 number, since 3×17645047699421³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17645047699121) 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, 8822523849710 + 8822523849711.

It is an arithmetic number, because the mean of its divisors is an integer number (8822523849711).

Almost surely, 2^{17645047699421} is an apocalyptic number.

It is an amenable number.

17645047699421 is a deficient number, since it is larger than the sum of its proper divisors (1).

17645047699421 is an equidigital number, since it uses as much as digits as its factorization.

17645047699421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 91445760, while the sum is 65.

The spelling of 17645047699421 in words is "seventeen trillion, six hundred forty-five billion, forty-seven million, six hundred ninety-nine thousand, four hundred twenty-one".