21794165 has 12 divisors (see below), whose sum is σ = 26816772. Its totient is φ = 17003520.

The previous prime is 21794137. The next prime is 21794173. The reversal of 21794165 is 56149712.

It can be written as a sum of positive squares in 6 ways, for example, as 6599761 + 15194404 = 2569^2 + 3898^2 .

It is not a de Polignac number, because 21794165 - 2⁸ = 21793909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7109 + ... + 9701.

It is an arithmetic number, because the mean of its divisors is an integer number (2234731).

Almost surely, 2^21794165 is an apocalyptic number.

It is an amenable number.

21794165 is a deficient number, since it is larger than the sum of its proper divisors (5022607).

21794165 is an equidigital number, since it uses as much as digits as its factorization.

21794165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2680 (or 2639 counting only the distinct ones).

The product of its digits is 15120, while the sum is 35.

The square root of 21794165 is about 4668.4221103067. The cubic root of 21794165 is about 279.3273180422.

The spelling of 21794165 in words is "twenty-one million, seven hundred ninety-four thousand, one hundred sixty-five".