198557531 has 4 divisors (see below), whose sum is σ = 203175192. Its totient is φ = 193939872.

The previous prime is 198557507. The next prime is 198557533. The reversal of 198557531 is 135755891.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 135755891 = 79 ⋅1718429.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198557531 is a prime.

It is a super-2 number, since 2×198557531² = 78850186233631922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198557533) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2308766 + ... + 2308851.

It is an arithmetic number, because the mean of its divisors is an integer number (50793798).

Almost surely, 2^198557531 is an apocalyptic number.

198557531 is a deficient number, since it is larger than the sum of its proper divisors (4617661).

198557531 is an equidigital number, since it uses as much as digits as its factorization.

198557531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4617660.

The product of its digits is 189000, while the sum is 44.

The square root of 198557531 is about 14091.0443544827. The cubic root of 198557531 is about 583.3942190235.

The spelling of 198557531 in words is "one hundred ninety-eight million, five hundred fifty-seven thousand, five hundred thirty-one".