161610517 has 4 divisors (see below), whose sum is σ = 171117036. Its totient is φ = 152104000.

The previous prime is 161610511. The next prime is 161610557. The reversal of 161610517 is 715016161.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 83923921 + 77686596 = 9161^2 + 8814^2 .

It is a cyclic number.

It is not a de Polignac number, because 161610517 - 2³ = 161610509 is a prime.

It is a super-2 number, since 2×161610517² = 52235918410014578, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161610511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4753234 + ... + 4753267.

It is an arithmetic number, because the mean of its divisors is an integer number (42779259).

Almost surely, 2^161610517 is an apocalyptic number.

161610517 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

161610517 is a deficient number, since it is larger than the sum of its proper divisors (9506519).

161610517 is an equidigital number, since it uses as much as digits as its factorization.

161610517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9506518.

The product of its (nonzero) digits is 1260, while the sum is 28.

The square root of 161610517 is about 12712.6125167095. The cubic root of 161610517 is about 544.6989522180.

Adding to 161610517 its reverse (715016161), we get a palindrome (876626678).

The spelling of 161610517 in words is "one hundred sixty-one million, six hundred ten thousand, five hundred seventeen".