161766725 has 12 divisors (see below), whose sum is σ = 200968164. Its totient is φ = 129169920.

The previous prime is 161766719. The next prime is 161766757. The reversal of 161766725 is 527667161.

It can be written as a sum of positive squares in 6 ways, for example, as 32330596 + 129436129 = 5686^2 + 11377^2 .

It is not a de Polignac number, because 161766725 - 2²⁰ = 160718149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 8117 + ... + 19733.

It is an arithmetic number, because the mean of its divisors is an integer number (16747347).

Almost surely, 2^161766725 is an apocalyptic number.

It is an amenable number.

161766725 is a deficient number, since it is larger than the sum of its proper divisors (39201439).

161766725 is a wasteful number, since it uses less digits than its factorization.

161766725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12184 (or 12179 counting only the distinct ones).

The product of its digits is 105840, while the sum is 41.

The square root of 161766725 is about 12718.7548525789. The cubic root of 161766725 is about 544.8743923981.

The spelling of 161766725 in words is "one hundred sixty-one million, seven hundred sixty-six thousand, seven hundred twenty-five".