161038509 has 16 divisors (see below), whose sum is σ = 228748800. Its totient is φ = 100480176.

The previous prime is 161038489. The next prime is 161038517. The reversal of 161038509 is 905830161.

It is not a de Polignac number, because 161038509 - 2⁵ = 161038477 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 161038509.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161038519) 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, 12289 + ... + 21750.

It is an arithmetic number, because the mean of its divisors is an integer number (14296800).

Almost surely, 2^161038509 is an apocalyptic number.

161038509 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

161038509 is a deficient number, since it is larger than the sum of its proper divisors (67710291).

161038509 is a wasteful number, since it uses less digits than its factorization.

161038509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34144.

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 161038509 is about 12690.0949169027. The cubic root of 161038509 is about 544.0555525106.

The spelling of 161038509 in words is "one hundred sixty-one million, thirty-eight thousand, five hundred nine".