18161709 has 16 divisors (see below), whose sum is σ = 25080000. Its totient is φ = 11681280.

The previous prime is 18161707. The next prime is 18161711. The reversal of 18161709 is 90716181.

It is an interprime number because it is at equal distance from previous prime (18161707) and next prime (18161711).

It is not a de Polignac number, because 18161709 - 2¹ = 18161707 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18161709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18161707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13917 + ... + 15165.

It is an arithmetic number, because the mean of its divisors is an integer number (1567500).

Almost surely, 2^18161709 is an apocalyptic number.

It is an amenable number.

18161709 is a deficient number, since it is larger than the sum of its proper divisors (6918291).

18161709 is a wasteful number, since it uses less digits than its factorization.

18161709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1420.

The product of its (nonzero) digits is 3024, while the sum is 33.

The square root of 18161709 is about 4261.6556641756. The cubic root of 18161709 is about 262.8566110097.

The spelling of 18161709 in words is "eighteen million, one hundred sixty-one thousand, seven hundred nine".