195387221 has 2 divisors, whose sum is σ = 195387222. Its totient is φ = 195387220.

The previous prime is 195387191. The next prime is 195387259. The reversal of 195387221 is 122783591.

It is an a-pointer prime, because the next prime (195387259) can be obtained adding 195387221 to its sum of digits (38).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 144336196 + 51051025 = 12014^2 + 7145^2 .

It is a cyclic number.

It is not a de Polignac number, because 195387221 - 2²⁶ = 128278357 is a prime.

It is a super-2 number, since 2×195387221² = 76352332260205682, which contains 22 as substring.

It is a Chen prime.

It is a plaindrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (195387421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97693610 + 97693611.

It is an arithmetic number, because the mean of its divisors is an integer number (97693611).

Almost surely, 2^195387221 is an apocalyptic number.

It is an amenable number.

195387221 is a deficient number, since it is larger than the sum of its proper divisors (1).

195387221 is an equidigital number, since it uses as much as digits as its factorization.

195387221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30240, while the sum is 38.

The square root of 195387221 is about 13978.0979035060. The cubic root of 195387221 is about 580.2725839222.

The spelling of 195387221 in words is "one hundred ninety-five million, three hundred eighty-seven thousand, two hundred twenty-one".