198971623 has 2 divisors, whose sum is σ = 198971624. Its totient is φ = 198971622.

The previous prime is 198971611. The next prime is 198971651. The reversal of 198971623 is 326179891.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 198971623 - 2²¹ = 196874471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198971603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99485811 + 99485812.

It is an arithmetic number, because the mean of its divisors is an integer number (99485812).

Almost surely, 2^198971623 is an apocalyptic number.

198971623 is a deficient number, since it is larger than the sum of its proper divisors (1).

198971623 is an equidigital number, since it uses as much as digits as its factorization.

198971623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 46.

The square root of 198971623 is about 14105.7301477095. The cubic root of 198971623 is about 583.7994938983.

The spelling of 198971623 in words is "one hundred ninety-eight million, nine hundred seventy-one thousand, six hundred twenty-three".