194399957 has 2 divisors, whose sum is σ = 194399958. Its totient is φ = 194399956.

The previous prime is 194399951. The next prime is 194399969. The reversal of 194399957 is 759993491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182628196 + 11771761 = 13514^2 + 3431^2 .

It is an emirp because it is prime and its reverse (759993491) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 194399957 - 2⁶ = 194399893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194399951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97199978 + 97199979.

It is an arithmetic number, because the mean of its divisors is an integer number (97199979).

Almost surely, 2^194399957 is an apocalyptic number.

It is an amenable number.

194399957 is a deficient number, since it is larger than the sum of its proper divisors (1).

194399957 is an equidigital number, since it uses as much as digits as its factorization.

194399957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2755620, while the sum is 56.

The square root of 194399957 is about 13942.7385043255. The cubic root of 194399957 is about 579.2935880514.

The spelling of 194399957 in words is "one hundred ninety-four million, three hundred ninety-nine thousand, nine hundred fifty-seven".