19943172377 has 2 divisors, whose sum is σ = 19943172378. Its totient is φ = 19943172376.

The previous prime is 19943172341. The next prime is 19943172391. The reversal of 19943172377 is 77327134991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17629466176 + 2313706201 = 132776^2 + 48101^2 .

It is a cyclic number.

It is not a de Polignac number, because 19943172377 - 2⁸ = 19943172121 is a prime.

It is not a weakly prime, because it can be changed into another prime (19943472377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9971586188 + 9971586189.

It is an arithmetic number, because the mean of its divisors is an integer number (9971586189).

Almost surely, 2^19943172377 is an apocalyptic number.

It is an amenable number.

19943172377 is a deficient number, since it is larger than the sum of its proper divisors (1).

19943172377 is an equidigital number, since it uses as much as digits as its factorization.

19943172377 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2000376, while the sum is 53.

The spelling of 19943172377 in words is "nineteen billion, nine hundred forty-three million, one hundred seventy-two thousand, three hundred seventy-seven".