198186122761 has 9 divisors (see below), whose sum is σ = 217846327629. Its totient is φ = 180164750700.

The previous prime is 198186122753. The next prime is 198186122801. The reversal of 198186122761 is 167221681891.

The square root of 198186122761 is 445181.

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

It is not a de Polignac number, because 198186122761 - 2³ = 198186122753 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 198186122699 and 198186122708.

It is not an unprimeable number, because it can be changed into a prime (198186122731) 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, 4876756 + ... + 4917226.

Almost surely, 2^198186122761 is an apocalyptic number.

198186122761 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

198186122761 is the 445181-st square number.

198186122761 is the 222591-st centered octagonal number.

It is an amenable number.

198186122761 is a deficient number, since it is larger than the sum of its proper divisors (19660204868).

198186122761 is an frugal number, since it uses more digits than its factorization.

198186122761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80964 (or 40482 counting only the distinct ones).

The product of its digits is 580608, while the sum is 52.

The spelling of 198186122761 in words is "one hundred ninety-eight billion, one hundred eighty-six million, one hundred twenty-two thousand, seven hundred sixty-one".