195923972689 has 3 divisors (see below), whose sum is σ = 195924415323. Its totient is φ = 195923530056.

The previous prime is 195923972677. The next prime is 195923972693. The reversal of 195923972689 is 986279329591.

The square root of 195923972689 is 442633.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 136090899025 + 59833073664 = 368905^2 + 244608^2 .

It is not a de Polignac number, because 195923972689 - 2²¹ = 195921875537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (195923972789) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 221317 + ... + 663949.

It is an arithmetic number, because the mean of its divisors is an integer number (65308138441).

Almost surely, 2^195923972689 is an apocalyptic number.

195923972689 is the 442633-rd square number.

195923972689 is the 221317-th centered octagonal number.

It is an amenable number.

195923972689 is a deficient number, since it is larger than the sum of its proper divisors (442634).

195923972689 is an frugal number, since it uses more digits than its factorization.

195923972689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 885266 (or 442633 counting only the distinct ones).

The product of its digits is 132269760, while the sum is 70.

The spelling of 195923972689 in words is "one hundred ninety-five billion, nine hundred twenty-three million, nine hundred seventy-two thousand, six hundred eighty-nine".