163661325 has 24 divisors (see below), whose sum is σ = 271807008. Its totient is φ = 86892480.

The previous prime is 163661317. The next prime is 163661327. The reversal of 163661325 is 523166361.

It is not a de Polignac number, because 163661325 - 2³ = 163661317 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (163661327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12219 + ... + 21831.

It is an arithmetic number, because the mean of its divisors is an integer number (11325292).

Almost surely, 2^163661325 is an apocalyptic number.

163661325 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

163661325 is a deficient number, since it is larger than the sum of its proper divisors (108145683).

163661325 is a wasteful number, since it uses less digits than its factorization.

163661325 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9853 (or 9848 counting only the distinct ones).

The product of its digits is 19440, while the sum is 33.

The square root of 163661325 is about 12793.0186039105. The cubic root of 163661325 is about 546.9933178556.

The spelling of 163661325 in words is "one hundred sixty-three million, six hundred sixty-one thousand, three hundred twenty-five".