198156139 has 2 divisors, whose sum is σ = 198156140. Its totient is φ = 198156138.

The previous prime is 198156113. The next prime is 198156151. The reversal of 198156139 is 931651891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 198156139 - 2⁷ = 198156011 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 198156095 and 198156104.

It is not a weakly prime, because it can be changed into another prime (198159139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99078069 + 99078070.

It is an arithmetic number, because the mean of its divisors is an integer number (99078070).

Almost surely, 2^198156139 is an apocalyptic number.

198156139 is a deficient number, since it is larger than the sum of its proper divisors (1).

198156139 is an equidigital number, since it uses as much as digits as its factorization.

198156139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58320, while the sum is 43.

The square root of 198156139 is about 14076.7943438838. The cubic root of 198156139 is about 583.0008355657. Note that the first 3 decimals are identical.

The spelling of 198156139 in words is "one hundred ninety-eight million, one hundred fifty-six thousand, one hundred thirty-nine".