198897551 has 2 divisors, whose sum is σ = 198897552. Its totient is φ = 198897550.

The previous prime is 198897547. The next prime is 198897577. The reversal of 198897551 is 155798891.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 198897551 - 2² = 198897547 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 198897493 and 198897502.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198897521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99448775 + 99448776.

It is an arithmetic number, because the mean of its divisors is an integer number (99448776).

Almost surely, 2^198897551 is an apocalyptic number.

198897551 is a deficient number, since it is larger than the sum of its proper divisors (1).

198897551 is an equidigital number, since it uses as much as digits as its factorization.

198897551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 907200, while the sum is 53.

The square root of 198897551 is about 14103.1043036631. The cubic root of 198897551 is about 583.7270404119.

The spelling of 198897551 in words is "one hundred ninety-eight million, eight hundred ninety-seven thousand, five hundred fifty-one".