198157977 has 12 divisors (see below), whose sum is σ = 293964580. Its totient is φ = 128534688.

The previous prime is 198157963. The next prime is 198157997. The reversal of 198157977 is 779751891.

It can be written as a sum of positive squares in 2 ways, for example, as 102333456 + 95824521 = 10116^2 + 9789^2 .

It is not a de Polignac number, because 198157977 - 2⁶ = 198157913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198157997) 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 11 ways as a sum of consecutive naturals, for example, 297202 + ... + 297867.

Almost surely, 2^198157977 is an apocalyptic number.

It is an amenable number.

198157977 is a deficient number, since it is larger than the sum of its proper divisors (95806603).

198157977 is a wasteful number, since it uses less digits than its factorization.

198157977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595112 (or 595109 counting only the distinct ones).

The product of its digits is 1111320, while the sum is 54.

The square root of 198157977 is about 14076.8596284825. The cubic root of 198157977 is about 583.0026381042.

The spelling of 198157977 in words is "one hundred ninety-eight million, one hundred fifty-seven thousand, nine hundred seventy-seven".