194939887 has 2 divisors, whose sum is σ = 194939888. Its totient is φ = 194939886.

The previous prime is 194939863. The next prime is 194939909. The reversal of 194939887 is 788939491.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 194939887 - 2²³ = 186551279 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194939807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97469943 + 97469944.

It is an arithmetic number, because the mean of its divisors is an integer number (97469944).

Almost surely, 2^194939887 is an apocalyptic number.

194939887 is a deficient number, since it is larger than the sum of its proper divisors (1).

194939887 is an equidigital number, since it uses as much as digits as its factorization.

194939887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3919104, while the sum is 58.

The square root of 194939887 is about 13962.0874871919. The cubic root of 194939887 is about 579.8294058332.

It can be divided in two parts, 19493 and 9887, that multiplied together give a palindrome (192727291).

The spelling of 194939887 in words is "one hundred ninety-four million, nine hundred thirty-nine thousand, eight hundred eighty-seven".