198040637 has 2 divisors, whose sum is σ = 198040638. Its totient is φ = 198040636.

The previous prime is 198040571. The next prime is 198040643. The reversal of 198040637 is 736040891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 181872196 + 16168441 = 13486^2 + 4021^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198040637 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 198040637.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198040697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99020318 + 99020319.

It is an arithmetic number, because the mean of its divisors is an integer number (99020319).

Almost surely, 2^198040637 is an apocalyptic number.

It is an amenable number.

198040637 is a deficient number, since it is larger than the sum of its proper divisors (1).

198040637 is an equidigital number, since it uses as much as digits as its factorization.

198040637 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 38.

The square root of 198040637 is about 14072.6911783070. The cubic root of 198040637 is about 582.8875396392.

The spelling of 198040637 in words is "one hundred ninety-eight million, forty thousand, six hundred thirty-seven".