161717725 has 24 divisors (see below), whose sum is σ = 218097152. Its totient is φ = 118238400.

The previous prime is 161717723. The next prime is 161717737. The reversal of 161717725 is 527717161.

It is not a de Polignac number, because 161717725 - 2¹ = 161717723 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161717723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31060 + ... + 35890.

Almost surely, 2^161717725 is an apocalyptic number.

It is an amenable number.

161717725 is a deficient number, since it is larger than the sum of its proper divisors (56379427).

161717725 is a wasteful number, since it uses less digits than its factorization.

161717725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4957 (or 4952 counting only the distinct ones).

The product of its digits is 20580, while the sum is 37.

The square root of 161717725 is about 12716.8284174947. The cubic root of 161717725 is about 544.8193717268.

The spelling of 161717725 in words is "one hundred sixty-one million, seven hundred seventeen thousand, seven hundred twenty-five".