21794 has 8 divisors (see below), whose sum is σ = 34668. Its totient is φ = 10240.

The previous prime is 21787. The next prime is 21799. The reversal of 21794 is 49712.

It can be written as a sum of positive squares in 2 ways, for example, as 18769 + 3025 = 137^2 + 55^2 .

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

It is an Ulam number.

It is a plaindrome in base 15.

It is a nialpdrome in base 16.

It is a zygodrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (21799) 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, 287 + ... + 354.

2²¹⁷⁹⁴ is an apocalyptic number.

21794 is a deficient number, since it is larger than the sum of its proper divisors (12874).

21794 is a wasteful number, since it uses less digits than its factorization.

21794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660.

The product of its digits is 504, while the sum is 23.

The square root of 21794 is about 147.6279106402. The cubic root of 21794 is about 27.9326613127.

The spelling of 21794 in words is "twenty-one thousand, seven hundred ninety-four".