161711109 has 48 divisors (see below), whose sum is σ = 286416000. Its totient is φ = 85857408.

The previous prime is 161711107. The next prime is 161711111. The reversal of 161711109 is 901117161.

It is an interprime number because it is at equal distance from previous prime (161711107) and next prime (161711111).

It is not a de Polignac number, because 161711109 - 2¹ = 161711107 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161711107) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 62167 + ... + 64715.

It is an arithmetic number, because the mean of its divisors is an integer number (5967000).

Almost surely, 2^161711109 is an apocalyptic number.

161711109 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

161711109 is a deficient number, since it is larger than the sum of its proper divisors (124704891).

161711109 is a wasteful number, since it uses less digits than its factorization.

161711109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2634 (or 2631 counting only the distinct ones).

The product of its (nonzero) digits is 378, while the sum is 27.

The square root of 161711109 is about 12716.5682870812. The cubic root of 161711109 is about 544.8119419617.

The spelling of 161711109 in words is "one hundred sixty-one million, seven hundred eleven thousand, one hundred nine".