198439898651 has 2 divisors, whose sum is σ = 198439898652. Its totient is φ = 198439898650.

The previous prime is 198439898623. The next prime is 198439898653. The reversal of 198439898651 is 156898934891.

It is a strong prime.

It is an emirp because it is prime and its reverse (156898934891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 198439898651 - 2¹⁰ = 198439897627 is a prime.

Together with 198439898653, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (198439898653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99219949325 + 99219949326.

It is an arithmetic number, because the mean of its divisors is an integer number (99219949326).

Almost surely, 2^198439898651 is an apocalyptic number.

198439898651 is a deficient number, since it is larger than the sum of its proper divisors (1).

198439898651 is an equidigital number, since it uses as much as digits as its factorization.

198439898651 is an evil number, because the sum of its binary digits is even.

The product of its digits is 134369280, while the sum is 71.

The spelling of 198439898651 in words is "one hundred ninety-eight billion, four hundred thirty-nine million, eight hundred ninety-eight thousand, six hundred fifty-one".