161327711978 has 8 divisors (see below), whose sum is σ = 243615672900. Its totient is φ = 80122487680.

The previous prime is 161327711939. The next prime is 161327712019. The reversal of 161327711978 is 879117723161.

It can be written as a sum of positive squares in 2 ways, for example, as 127972899289 + 33354812689 = 357733^2 + 182633^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 270683783 + ... + 270684378.

Almost surely, 2^161327711978 is an apocalyptic number.

161327711978 is a deficient number, since it is larger than the sum of its proper divisors (82287960922).

161327711978 is a wasteful number, since it uses less digits than its factorization.

161327711978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541368312.

The product of its digits is 889056, while the sum is 53.

The spelling of 161327711978 in words is "one hundred sixty-one billion, three hundred twenty-seven million, seven hundred eleven thousand, nine hundred seventy-eight".