194459989 has 2 divisors, whose sum is σ = 194459990. Its totient is φ = 194459988.

The previous prime is 194459971. The next prime is 194460017. The reversal of 194459989 is 989954491.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 168143089 + 26316900 = 12967^2 + 5130^2 .

It is a cyclic number.

It is not a de Polignac number, because 194459989 - 2⁷ = 194459861 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194459939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97229994 + 97229995.

It is an arithmetic number, because the mean of its divisors is an integer number (97229995).

Almost surely, 2^194459989 is an apocalyptic number.

It is an amenable number.

194459989 is a deficient number, since it is larger than the sum of its proper divisors (1).

194459989 is an equidigital number, since it uses as much as digits as its factorization.

194459989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4199040, while the sum is 58.

The square root of 194459989 is about 13944.8911433543. The cubic root of 194459989 is about 579.3532118190.

The spelling of 194459989 in words is "one hundred ninety-four million, four hundred fifty-nine thousand, nine hundred eighty-nine".