194455391 has 4 divisors (see below), whose sum is σ = 209413512. Its totient is φ = 179497272.

The previous prime is 194455379. The next prime is 194455423. The reversal of 194455391 is 193554491.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 194455391 - 2¹⁸ = 194193247 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (194455361) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7479041 + ... + 7479066.

It is an arithmetic number, because the mean of its divisors is an integer number (52353378).

Almost surely, 2^194455391 is an apocalyptic number.

194455391 is a deficient number, since it is larger than the sum of its proper divisors (14958121).

194455391 is a wasteful number, since it uses less digits than its factorization.

194455391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14958120.

The product of its digits is 97200, while the sum is 41.

The square root of 194455391 is about 13944.7262791351. The cubic root of 194455391 is about 579.3486455205.

The spelling of 194455391 in words is "one hundred ninety-four million, four hundred fifty-five thousand, three hundred ninety-one".