21905034 has 48 divisors (see below), whose sum is σ = 47187360. Its totient is φ = 6770400.

The previous prime is 21905011. The next prime is 21905053. The reversal of 21905034 is 43050912.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21904995 and 21905013.

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 23 ways as a sum of consecutive naturals, for example, 167149 + ... + 167279.

It is an arithmetic number, because the mean of its divisors is an integer number (983070).

Almost surely, 2^21905034 is an apocalyptic number.

21905034 is an abundant number, since it is smaller than the sum of its proper divisors (25282326).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21905034 is a wasteful number, since it uses less digits than its factorization.

21905034 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227 (or 196 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 24.

The square root of 21905034 is about 4680.2814017963. The cubic root of 21905034 is about 279.8001720483.

Adding to 21905034 its reverse (43050912), we get a palindrome (64955946).

The spelling of 21905034 in words is "twenty-one million, nine hundred five thousand, thirty-four".