198719857 has 16 divisors (see below), whose sum is σ = 230244352. Its totient is φ = 167994000.

The previous prime is 198719849. The next prime is 198719869. The reversal of 198719857 is 758917891.

It is a cyclic number.

It is not a de Polignac number, because 198719857 - 2³ = 198719849 is a prime.

It is a super-2 number, since 2×198719857² = 78979163132200898, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 198719798 and 198719807.

It is not an unprimeable number, because it can be changed into a prime (198719837) 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, 264232 + ... + 264982.

It is an arithmetic number, because the mean of its divisors is an integer number (14390272).

Almost surely, 2^198719857 is an apocalyptic number.

It is an amenable number.

198719857 is a deficient number, since it is larger than the sum of its proper divisors (31524495).

198719857 is a wasteful number, since it uses less digits than its factorization.

198719857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1228.

The product of its digits is 1270080, while the sum is 55.

The square root of 198719857 is about 14096.8030772938. The cubic root of 198719857 is about 583.5531557552.

The spelling of 198719857 in words is "one hundred ninety-eight million, seven hundred nineteen thousand, eight hundred fifty-seven".