17640640445 has 4 divisors (see below), whose sum is σ = 21168768540. Its totient is φ = 14112512352.

The previous prime is 17640640439. The next prime is 17640640477. The reversal of 17640640445 is 54404604671.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 54404604671 = 17 ⋅3200270863.

It can be written as a sum of positive squares in 2 ways, for example, as 6368359204 + 11272281241 = 79802^2 + 106171^2 .

It is a cyclic number.

It is not a de Polignac number, because 17640640445 - 2¹⁴ = 17640624061 is a prime.

It is a super-2 number, since 2×17640640445² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1764064040 + ... + 1764064049.

It is an arithmetic number, because the mean of its divisors is an integer number (5292192135).

Almost surely, 2^17640640445 is an apocalyptic number.

It is an amenable number.

17640640445 is a deficient number, since it is larger than the sum of its proper divisors (3528128095).

17640640445 is an equidigital number, since it uses as much as digits as its factorization.

17640640445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3528128094.

The product of its (nonzero) digits is 322560, while the sum is 41.

The spelling of 17640640445 in words is "seventeen billion, six hundred forty million, six hundred forty thousand, four hundred forty-five".