161843787 has 24 divisors (see below), whose sum is σ = 273388544. Its totient is φ = 90329904.

The previous prime is 161843779. The next prime is 161843807. The reversal of 161843787 is 787348161.

It is not a de Polignac number, because 161843787 - 2³ = 161843779 is a prime.

It is a super-2 number, since 2×161843787² = 52386822781002738, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161843887) 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 23 ways as a sum of consecutive naturals, for example, 27163 + ... + 32580.

Almost surely, 2^161843787 is an apocalyptic number.

161843787 is a deficient number, since it is larger than the sum of its proper divisors (111544757).

161843787 is a wasteful number, since it uses less digits than its factorization.

161843787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59799 (or 59796 counting only the distinct ones).

The product of its digits is 225792, while the sum is 45.

The square root of 161843787 is about 12721.7839550906. The cubic root of 161843787 is about 544.9609005982.

It can be divided in two parts, 16 and 1843787, that multiplied together give a palindrome (29500592).

The spelling of 161843787 in words is "one hundred sixty-one million, eight hundred forty-three thousand, seven hundred eighty-seven".