196505509 has 2 divisors, whose sum is σ = 196505510. Its totient is φ = 196505508.

The previous prime is 196505489. The next prime is 196505513. The reversal of 196505509 is 905505691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149377284 + 47128225 = 12222^2 + 6865^2 .

It is a cyclic number.

It is not a de Polignac number, because 196505509 - 2²⁷ = 62287781 is a prime.

It is a super-2 number, since 2×196505509² = 77228830134698162, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (196505599) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98252754 + 98252755.

It is an arithmetic number, because the mean of its divisors is an integer number (98252755).

Almost surely, 2^196505509 is an apocalyptic number.

It is an amenable number.

196505509 is a deficient number, since it is larger than the sum of its proper divisors (1).

196505509 is an equidigital number, since it uses as much as digits as its factorization.

196505509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60750, while the sum is 40.

The square root of 196505509 is about 14018.0422670215. The cubic root of 196505509 is about 581.3775312873.

The spelling of 196505509 in words is "one hundred ninety-six million, five hundred five thousand, five hundred nine".