17643324661 has 2 divisors, whose sum is σ = 17643324662. Its totient is φ = 17643324660.

The previous prime is 17643324653. The next prime is 17643324697. The reversal of 17643324661 is 16642334671.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15284376900 + 2358947761 = 123630^2 + 48569^2 .

It is a cyclic number.

It is not a de Polignac number, because 17643324661 - 2³ = 17643324653 is a prime.

It is a super-2 number, since 2×17643324661² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (17643324641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8821662330 + 8821662331.

It is an arithmetic number, because the mean of its divisors is an integer number (8821662331).

Almost surely, 2^17643324661 is an apocalyptic number.

It is an amenable number.

17643324661 is a deficient number, since it is larger than the sum of its proper divisors (1).

17643324661 is an equidigital number, since it uses as much as digits as its factorization.

17643324661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 43.

The spelling of 17643324661 in words is "seventeen billion, six hundred forty-three million, three hundred twenty-four thousand, six hundred sixty-one".