17720045 has 16 divisors (see below), whose sum is σ = 24401280. Its totient is φ = 12101184.

The previous prime is 17720041. The next prime is 17720063. The reversal of 17720045 is 54002771.

It is a cyclic number.

It is not a de Polignac number, because 17720045 - 2² = 17720041 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 17719996 and 17720023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17720041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9011 + ... + 10799.

It is an arithmetic number, because the mean of its divisors is an integer number (1525080).

Almost surely, 2^17720045 is an apocalyptic number.

It is an amenable number.

17720045 is a deficient number, since it is larger than the sum of its proper divisors (6681235).

17720045 is a wasteful number, since it uses less digits than its factorization.

17720045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2084.

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 17720045 is about 4209.5183810027. The cubic root of 17720045 is about 260.7083494703.

The spelling of 17720045 in words is "seventeen million, seven hundred twenty thousand, forty-five".