199940537 has 2 divisors, whose sum is σ = 199940538. Its totient is φ = 199940536.

The previous prime is 199940479. The next prime is 199940549. The reversal of 199940537 is 735049991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 160300921 + 39639616 = 12661^2 + 6296^2 .

It is a cyclic number.

It is not a de Polignac number, because 199940537 - 2²⁰ = 198891961 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 199940491 and 199940500.

It is not a weakly prime, because it can be changed into another prime (199948537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99970268 + 99970269.

It is an arithmetic number, because the mean of its divisors is an integer number (99970269).

Almost surely, 2^199940537 is an apocalyptic number.

It is an amenable number.

199940537 is a deficient number, since it is larger than the sum of its proper divisors (1).

199940537 is an equidigital number, since it uses as much as digits as its factorization.

199940537 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 306180, while the sum is 47.

The square root of 199940537 is about 14140.0331329173. The cubic root of 199940537 is about 584.7455849422.

The spelling of 199940537 in words is "one hundred ninety-nine million, nine hundred forty thousand, five hundred thirty-seven".