161725118 has 4 divisors (see below), whose sum is σ = 242587680. Its totient is φ = 80862558.

The previous prime is 161725117. The next prime is 161725127. The reversal of 161725118 is 811527161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 811527161 = 419 ⋅1936819.

It is a super-2 number, since 2×161725118² = 52310027584227848, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161725117) 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 as a sum of consecutive naturals, namely, 40431278 + ... + 40431281.

It is an arithmetic number, because the mean of its divisors is an integer number (60646920).

Almost surely, 2^161725118 is an apocalyptic number.

161725118 is a deficient number, since it is larger than the sum of its proper divisors (80862562).

161725118 is an equidigital number, since it uses as much as digits as its factorization.

161725118 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80862561.

The product of its digits is 3360, while the sum is 32.

The square root of 161725118 is about 12717.1190919956. The cubic root of 161725118 is about 544.8276738228.

The spelling of 161725118 in words is "one hundred sixty-one million, seven hundred twenty-five thousand, one hundred eighteen".