198406557 has 24 divisors (see below), whose sum is σ = 299143680. Its totient is φ = 129967560.

The previous prime is 198406553. The next prime is 198406561. The reversal of 198406557 is 755604891.

198406557 is a `hidden beast` number, since 1 + 98 + 4 + 0 + 6 + 557 = 666.

It is an interprime number because it is at equal distance from previous prime (198406553) and next prime (198406561).

It is not a de Polignac number, because 198406557 - 2² = 198406553 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198406553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92932 + ... + 95042.

It is an arithmetic number, because the mean of its divisors is an integer number (12464320).

Almost surely, 2^198406557 is an apocalyptic number.

It is an amenable number.

198406557 is a deficient number, since it is larger than the sum of its proper divisors (100737123).

198406557 is an equidigital number, since it uses as much as digits as its factorization.

198406557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2238 (or 2173 counting only the distinct ones).

The product of its (nonzero) digits is 302400, while the sum is 45.

The square root of 198406557 is about 14085.6862452633. The cubic root of 198406557 is about 583.2463195018.

The spelling of 198406557 in words is "one hundred ninety-eight million, four hundred six thousand, five hundred fifty-seven".