198811557 has 16 divisors (see below), whose sum is σ = 336612480. Its totient is φ = 113606496.

The previous prime is 198811519. The next prime is 198811577. The reversal of 198811557 is 755118891.

198811557 is a `hidden beast` number, since 1 + 9 + 88 + 11 + 557 = 666.

It is not a de Polignac number, because 198811557 - 2⁷ = 198811429 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198811507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 525768 + ... + 526145.

It is an arithmetic number, because the mean of its divisors is an integer number (21038280).

Almost surely, 2^198811557 is an apocalyptic number.

It is an amenable number.

198811557 is a deficient number, since it is larger than the sum of its proper divisors (137800923).

198811557 is a wasteful number, since it uses less digits than its factorization.

198811557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1051929 (or 1051923 counting only the distinct ones).

The product of its digits is 100800, while the sum is 45.

The square root of 198811557 is about 14100.0552126579. The cubic root of 198811557 is about 583.6429028599.

The spelling of 198811557 in words is "one hundred ninety-eight million, eight hundred eleven thousand, five hundred fifty-seven".