194400021 has 8 divisors (see below), whose sum is σ = 268138080. Its totient is φ = 125130992.

The previous prime is 194399987. The next prime is 194400023. The reversal of 194400021 is 120004491.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 194400021 - 2⁶ = 194399957 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (194400023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1117155 + ... + 1117328.

It is an arithmetic number, because the mean of its divisors is an integer number (33517260).

Almost surely, 2^194400021 is an apocalyptic number.

It is an amenable number.

194400021 is a deficient number, since it is larger than the sum of its proper divisors (73738059).

194400021 is a wasteful number, since it uses less digits than its factorization.

194400021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2234515.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 194400021 is about 13942.7407994268. The cubic root of 194400021 is about 579.2936516227.

The spelling of 194400021 in words is "one hundred ninety-four million, four hundred thousand, twenty-one".