194372909 has 2 divisors, whose sum is σ = 194372910. Its totient is φ = 194372908.

The previous prime is 194372903. The next prime is 194372987. The reversal of 194372909 is 909273491.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 191822500 + 2550409 = 13850^2 + 1597^2 .

It is a cyclic number.

It is not a de Polignac number, because 194372909 - 2¹² = 194368813 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 194372909.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (194372903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97186454 + 97186455.

It is an arithmetic number, because the mean of its divisors is an integer number (97186455).

Almost surely, 2^194372909 is an apocalyptic number.

It is an amenable number.

194372909 is a deficient number, since it is larger than the sum of its proper divisors (1).

194372909 is an equidigital number, since it uses as much as digits as its factorization.

194372909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122472, while the sum is 44.

The square root of 194372909 is about 13941.7685033141. The cubic root of 194372909 is about 579.2667199732.

The spelling of 194372909 in words is "one hundred ninety-four million, three hundred seventy-two thousand, nine hundred nine".