198010861 has 2 divisors, whose sum is σ = 198010862. Its totient is φ = 198010860.

The previous prime is 198010793. The next prime is 198010873. The reversal of 198010861 is 168010891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152028900 + 45981961 = 12330^2 + 6781^2 .

It is a cyclic number.

It is not a de Polignac number, because 198010861 - 2¹³ = 198002669 is a prime.

It is a super-2 number, since 2×198010861² = 78416602147922642, which contains 22 as substring.

198010861 is a strobogrammatic number because it is the same when read upside-down.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198010961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99005430 + 99005431.

It is an arithmetic number, because the mean of its divisors is an integer number (99005431).

Almost surely, 2^198010861 is an apocalyptic number.

It is an amenable number.

198010861 is a deficient number, since it is larger than the sum of its proper divisors (1).

198010861 is an equidigital number, since it uses as much as digits as its factorization.

198010861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 34.

The square root of 198010861 is about 14071.6332030081. The cubic root of 198010861 is about 582.8583252154.

The spelling of 198010861 in words is "one hundred ninety-eight million, ten thousand, eight hundred sixty-one".