195505591 has 2 divisors, whose sum is σ = 195505592. Its totient is φ = 195505590.

The previous prime is 195505523. The next prime is 195505603.

195505591 is nontrivially palindromic in base 10.

It is a strong prime.

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 195505591 - 2¹⁷ = 195374519 is a prime.

It is a super-2 number, since 2×195505591² = 76444872224518562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195505511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97752795 + 97752796.

It is an arithmetic number, because the mean of its divisors is an integer number (97752796).

Almost surely, 2^195505591 is an apocalyptic number.

195505591 is a deficient number, since it is larger than the sum of its proper divisors (1).

195505591 is an equidigital number, since it uses as much as digits as its factorization.

195505591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 50625, while the sum is 40.

The square root of 195505591 is about 13982.3313864319. The cubic root of 195505591 is about 580.3897410208.

The spelling of 195505591 in words is "one hundred ninety-five million, five hundred five thousand, five hundred ninety-one".