21867814 has 16 divisors (see below), whose sum is σ = 35671968. Its totient is φ = 10012032.

The previous prime is 21867773. The next prime is 21867821. The reversal of 21867814 is 41876812.

It is a Harshad number since it is a multiple of its sum of digits (37).

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 7 ways as a sum of consecutive naturals, for example, 7434 + ... + 9949.

It is an arithmetic number, because the mean of its divisors is an integer number (2229498).

Almost surely, 2^21867814 is an apocalyptic number.

21867814 is a deficient number, since it is larger than the sum of its proper divisors (13804154).

21867814 is a wasteful number, since it uses less digits than its factorization.

21867814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17439.

The product of its digits is 21504, while the sum is 37.

The square root of 21867814 is about 4676.3034546530. The cubic root of 21867814 is about 279.6416077902.

It can be divided in two parts, 2186 and 7814, that added together give a 4-th power (10000 = 10⁴).

The spelling of 21867814 in words is "twenty-one million, eight hundred sixty-seven thousand, eight hundred fourteen".