198521137 has 2 divisors, whose sum is σ = 198521138. Its totient is φ = 198521136.

The previous prime is 198521111. The next prime is 198521149. The reversal of 198521137 is 731125891.

198521137 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 176252176 + 22268961 = 13276^2 + 4719^2 .

It is an emirp because it is prime and its reverse (731125891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 198521137 - 2⁷ = 198521009 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 198521096 and 198521105.

It is not a weakly prime, because it can be changed into another prime (198521107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99260568 + 99260569.

It is an arithmetic number, because the mean of its divisors is an integer number (99260569).

Almost surely, 2^198521137 is an apocalyptic number.

It is an amenable number.

198521137 is a deficient number, since it is larger than the sum of its proper divisors (1).

198521137 is an equidigital number, since it uses as much as digits as its factorization.

198521137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 15120, while the sum is 37.

The square root of 198521137 is about 14089.7529076986. The cubic root of 198521137 is about 583.3585730213.

The spelling of 198521137 in words is "one hundred ninety-eight million, five hundred twenty-one thousand, one hundred thirty-seven".