161935777779 has 12 divisors (see below), whose sum is σ = 229362325464. Its totient is φ = 101606761984.

The previous prime is 161935777771. The next prime is 161935777799. The reversal of 161935777779 is 977777539161.

It is not a de Polignac number, because 161935777779 - 2³ = 161935777771 is a prime.

It is a super-2 number, since 2×161935777779² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (161935777771) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 93387702 + ... + 93389435.

It is an arithmetic number, because the mean of its divisors is an integer number (19113527122).

Almost surely, 2^161935777779 is an apocalyptic number.

161935777779 is a deficient number, since it is larger than the sum of its proper divisors (67426547685).

161935777779 is a wasteful number, since it uses less digits than its factorization.

161935777779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186777174 (or 186777157 counting only the distinct ones).

The product of its digits is 122523030, while the sum is 69.

The spelling of 161935777779 in words is "one hundred sixty-one billion, nine hundred thirty-five million, seven hundred seventy-seven thousand, seven hundred seventy-nine".