161725 has 6 divisors (see below), whose sum is σ = 200570. Its totient is φ = 129360.

The previous prime is 161717. The next prime is 161729. The reversal of 161725 is 527161.

It can be written as a sum of positive squares in 3 ways, for example, as 121 + 161604 = 11^2 + 402^2 .

It is not a de Polignac number, because 161725 - 2³ = 161717 is a prime.

It is a plaindrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 161696 and 161705.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161729) 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 5 ways as a sum of consecutive naturals, for example, 3210 + ... + 3259.

2¹⁶¹⁷²⁵ is an apocalyptic number.

It is an amenable number.

161725 is a deficient number, since it is larger than the sum of its proper divisors (38845).

161725 is an equidigital number, since it uses as much as digits as its factorization.

161725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6479 (or 6474 counting only the distinct ones).

The product of its digits is 420, while the sum is 22.

The square root of 161725 is about 402.1504693520. The cubic root of 161725 is about 54.4827541315.

Adding to 161725 its reverse (527161), we get a palindrome (688886).

The spelling of 161725 in words is "one hundred sixty-one thousand, seven hundred twenty-five".