196320772561 has 9 divisors (see below), whose sum is σ = 196920312681. Its totient is φ = 195723056292.

The previous prime is 196320772517. The next prime is 196320772573. The reversal of 196320772561 is 165277023691.

The square root of 196320772561 is 443081.

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

It is not a de Polignac number, because 196320772561 - 2⁹ = 196320772049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (196320782561) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 249454210 + ... + 249454996.

Almost surely, 2^196320772561 is an apocalyptic number.

196320772561 is the 443081-st square number.

196320772561 is the 221541-st centered octagonal number.

It is an amenable number.

196320772561 is a deficient number, since it is larger than the sum of its proper divisors (599540120).

196320772561 is an frugal number, since it uses more digits than its factorization.

196320772561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2700 (or 1350 counting only the distinct ones).

The product of its (nonzero) digits is 952560, while the sum is 49.

Multiplying 196320772561 by its sum of digits (49), we get a square (9619717855489 = 3101567²).

The spelling of 196320772561 in words is "one hundred ninety-six billion, three hundred twenty million, seven hundred seventy-two thousand, five hundred sixty-one".