194863993 has 2 divisors, whose sum is σ = 194863994. Its totient is φ = 194863992.

The previous prime is 194863967. The next prime is 194864029. The reversal of 194863993 is 399368491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 151462249 + 43401744 = 12307^2 + 6588^2 .

It is a cyclic number.

It is not a de Polignac number, because 194863993 - 2¹⁷ = 194732921 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 194863993.

It is not a weakly prime, because it can be changed into another prime (194863393) 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, 97431996 + 97431997.

It is an arithmetic number, because the mean of its divisors is an integer number (97431997).

Almost surely, 2^194863993 is an apocalyptic number.

It is an amenable number.

194863993 is a deficient number, since it is larger than the sum of its proper divisors (1).

194863993 is an equidigital number, since it uses as much as digits as its factorization.

194863993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1259712, while the sum is 52.

The square root of 194863993 is about 13959.3693625464. The cubic root of 194863993 is about 579.7541496682.

The spelling of 194863993 in words is "one hundred ninety-four million, eight hundred sixty-three thousand, nine hundred ninety-three".