161989706000 has 80 divisors (see below), whose sum is σ = 412306527360. Its totient is φ = 61385558400.

The previous prime is 161989705967. The next prime is 161989706003. The reversal of 161989706000 is 607989161.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (161989706003) 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 in 15 ways as a sum of consecutive naturals, for example, 2093444 + ... + 2169443.

It is an arithmetic number, because the mean of its divisors is an integer number (5153831592).

Almost surely, 2^161989706000 is an apocalyptic number.

161989706000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161989706000 is an abundant number, since it is smaller than the sum of its proper divisors (250316821360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161989706000 is a wasteful number, since it uses less digits than its factorization.

161989706000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4262929 (or 4262913 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 47.

The spelling of 161989706000 in words is "one hundred sixty-one billion, nine hundred eighty-nine million, seven hundred six thousand".