195215987 has 2 divisors, whose sum is σ = 195215988. Its totient is φ = 195215986.

The previous prime is 195215963. The next prime is 195215989. The reversal of 195215987 is 789512591.

It is a happy number.

195215987 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 is a cyclic number.

It is not a de Polignac number, because 195215987 - 2¹⁶ = 195150451 is a prime.

Together with 195215989, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (195215989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97607993 + 97607994.

It is an arithmetic number, because the mean of its divisors is an integer number (97607994).

Almost surely, 2^195215987 is an apocalyptic number.

195215987 is a deficient number, since it is larger than the sum of its proper divisors (1).

195215987 is an equidigital number, since it uses as much as digits as its factorization.

195215987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 226800, while the sum is 47.

The square root of 195215987 is about 13971.9714786425. The cubic root of 195215987 is about 580.1030207410.

The spelling of 195215987 in words is "one hundred ninety-five million, two hundred fifteen thousand, nine hundred eighty-seven".