161781820708 has 12 divisors (see below), whose sum is σ = 285347464192. Its totient is φ = 80253973800.

The previous prime is 161781820687. The next prime is 161781820727. The reversal of 161781820708 is 807028187161.

161781820708 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (49) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 159233568 + ... + 159234583.

Almost surely, 2^161781820708 is an apocalyptic number.

It is an amenable number.

161781820708 is a deficient number, since it is larger than the sum of its proper divisors (123565643484).

161781820708 is a wasteful number, since it uses less digits than its factorization.

161781820708 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318468282 (or 318468280 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 49.

The spelling of 161781820708 in words is "one hundred sixty-one billion, seven hundred eighty-one million, eight hundred twenty thousand, seven hundred eight".