21040834 has 16 divisors (see below), whose sum is σ = 32760000. Its totient is φ = 10123344.

The previous prime is 21040807. The next prime is 21040879. The reversal of 21040834 is 43804012.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28579 + ... + 29305.

It is an arithmetic number, because the mean of its divisors is an integer number (2047500).

Almost surely, 2^21040834 is an apocalyptic number.

21040834 is a deficient number, since it is larger than the sum of its proper divisors (11719166).

21040834 is a wasteful number, since it uses less digits than its factorization.

21040834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1257.

The product of its (nonzero) digits is 768, while the sum is 22.

The square root of 21040834 is about 4587.0288858912. The cubic root of 21040834 is about 276.0711239371.

Adding to 21040834 its reverse (43804012), we get a palindrome (64844846).

The spelling of 21040834 in words is "twenty-one million, forty thousand, eight hundred thirty-four".