161987073 has 16 divisors (see below), whose sum is σ = 224870016. Its totient is φ = 103628160.

The previous prime is 161987071. The next prime is 161987093. The reversal of 161987073 is 370789161.

It is not a de Polignac number, because 161987073 - 2¹ = 161987071 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161987071) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1893 + ... + 18098.

It is an arithmetic number, because the mean of its divisors is an integer number (14054376).

Almost surely, 2^161987073 is an apocalyptic number.

It is an amenable number.

161987073 is a deficient number, since it is larger than the sum of its proper divisors (62882943).

161987073 is a wasteful number, since it uses less digits than its factorization.

161987073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20104.

The product of its (nonzero) digits is 63504, while the sum is 42.

The square root of 161987073 is about 12727.4142307069. The cubic root of 161987073 is about 545.1216775146.

The spelling of 161987073 in words is "one hundred sixty-one million, nine hundred eighty-seven thousand, seventy-three".