198694497541 has 2 divisors, whose sum is σ = 198694497542. Its totient is φ = 198694497540.

The previous prime is 198694497497. The next prime is 198694497601. The reversal of 198694497541 is 145794496891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 103365465025 + 95329032516 = 321505^2 + 308754^2 .

It is a cyclic number.

It is not a de Polignac number, because 198694497541 - 2¹³ = 198694489349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198694497041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99347248770 + 99347248771.

It is an arithmetic number, because the mean of its divisors is an integer number (99347248771).

Almost surely, 2^198694497541 is an apocalyptic number.

It is an amenable number.

198694497541 is a deficient number, since it is larger than the sum of its proper divisors (1).

198694497541 is an equidigital number, since it uses as much as digits as its factorization.

198694497541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 78382080, while the sum is 67.

The spelling of 198694497541 in words is "one hundred ninety-eight billion, six hundred ninety-four million, four hundred ninety-seven thousand, five hundred forty-one".