17640544897 has 2 divisors, whose sum is σ = 17640544898. Its totient is φ = 17640544896.

The previous prime is 17640544843. The next prime is 17640544903. The reversal of 17640544897 is 79844504671.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16390144576 + 1250400321 = 128024^2 + 35361^2 .

It is an emirp because it is prime and its reverse (79844504671) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 17640544897 - 2¹⁹ = 17640020609 is a prime.

It is a super-2 number, since 2×17640544897² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (17640544297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8820272448 + 8820272449.

It is an arithmetic number, because the mean of its divisors is an integer number (8820272449).

Almost surely, 2^17640544897 is an apocalyptic number.

It is an amenable number.

17640544897 is a deficient number, since it is larger than the sum of its proper divisors (1).

17640544897 is an equidigital number, since it uses as much as digits as its factorization.

17640544897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6773760, while the sum is 55.

The spelling of 17640544897 in words is "seventeen billion, six hundred forty million, five hundred forty-four thousand, eight hundred ninety-seven".