21412678 has 16 divisors (see below), whose sum is σ = 38304000. Its totient is φ = 8777736.

The previous prime is 21412663. The next prime is 21412679. The reversal of 21412678 is 87621412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21412679) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 32928 + ... + 33571.

It is an arithmetic number, because the mean of its divisors is an integer number (2394000).

Almost surely, 2^21412678 is an apocalyptic number.

21412678 is a deficient number, since it is larger than the sum of its proper divisors (16891322).

21412678 is a wasteful number, since it uses less digits than its factorization.

21412678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66531.

The product of its digits is 5376, while the sum is 31.

The square root of 21412678 is about 4627.3834939413. The cubic root of 21412678 is about 277.6879250837.

The spelling of 21412678 in words is "twenty-one million, four hundred twelve thousand, six hundred seventy-eight".