161823987 has 40 divisors (see below), whose sum is σ = 261865296. Its totient is φ = 98998848.

The previous prime is 161823979. The next prime is 161824001. The reversal of 161823987 is 789328161.

161823987 is a `hidden beast` number, since 1 + 618 + 23 + 9 + 8 + 7 = 666.

It is not a de Polignac number, because 161823987 - 2³ = 161823979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161823887) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 238693 + ... + 239369.

Almost surely, 2^161823987 is an apocalyptic number.

161823987 is a deficient number, since it is larger than the sum of its proper divisors (100041309).

161823987 is a wasteful number, since it uses less digits than its factorization.

161823987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 929 (or 920 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 161823987 is about 12721.0057385413. The cubic root of 161823987 is about 544.9386761514.

The spelling of 161823987 in words is "one hundred sixty-one million, eight hundred twenty-three thousand, nine hundred eighty-seven".