21194 has 4 divisors (see below), whose sum is σ = 31794. Its totient is φ = 10596.

The previous prime is 21193. The next prime is 21211. The reversal of 21194 is 49112.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 21025 + 169 = 145^2 + 13^2 .

It is a nialpdrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (21191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5297 + ... + 5300.

2²¹¹⁹⁴ is an apocalyptic number.

21194 is a deficient number, since it is larger than the sum of its proper divisors (10600).

21194 is a wasteful number, since it uses less digits than its factorization.

21194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10599.

The product of its digits is 72, while the sum is 17.

The square root of 21194 is about 145.5815922430. The cubic root of 21194 is about 27.6739388312.

The spelling of 21194 in words is "twenty-one thousand, one hundred ninety-four".