171984161977 has 2 divisors, whose sum is σ = 171984161978. Its totient is φ = 171984161976.

The previous prime is 171984161929. The next prime is 171984161989. The reversal of 171984161977 is 779161489171.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123310536336 + 48673625641 = 351156^2 + 220621^2 .

It is a cyclic number.

It is not a de Polignac number, because 171984161977 - 2⁷ = 171984161849 is a prime.

It is not a weakly prime, because it can be changed into another prime (171984161917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 85992080988 + 85992080989.

It is an arithmetic number, because the mean of its divisors is an integer number (85992080989).

Almost surely, 2^171984161977 is an apocalyptic number.

It is an amenable number.

171984161977 is a deficient number, since it is larger than the sum of its proper divisors (1).

171984161977 is an equidigital number, since it uses as much as digits as its factorization.

171984161977 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5334336, while the sum is 61.

The spelling of 171984161977 in words is "one hundred seventy-one billion, nine hundred eighty-four million, one hundred sixty-one thousand, nine hundred seventy-seven".