194388189761 has 2 divisors, whose sum is σ = 194388189762. Its totient is φ = 194388189760.

The previous prime is 194388189731. The next prime is 194388189767. The reversal of 194388189761 is 167981883491.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 182341810225 + 12046379536 = 427015^2 + 109756^2 .

It is a cyclic number.

It is not a de Polignac number, because 194388189761 - 2²⁶ = 194321080897 is a prime.

It is not a weakly prime, because it can be changed into another prime (194388189767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97194094880 + 97194094881.

It is an arithmetic number, because the mean of its divisors is an integer number (97194094881).

Almost surely, 2^194388189761 is an apocalyptic number.

It is an amenable number.

194388189761 is a deficient number, since it is larger than the sum of its proper divisors (1).

194388189761 is an equidigital number, since it uses as much as digits as its factorization.

194388189761 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20901888, while the sum is 65.

The spelling of 194388189761 in words is "one hundred ninety-four billion, three hundred eighty-eight million, one hundred eighty-nine thousand, seven hundred sixty-one".