21726814 has 4 divisors (see below), whose sum is σ = 32590224. Its totient is φ = 10863406.

The previous prime is 21726791. The next prime is 21726847. The reversal of 21726814 is 41862712.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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 as a sum of consecutive naturals, namely, 5431702 + ... + 5431705.

It is an arithmetic number, because the mean of its divisors is an integer number (8147556).

Almost surely, 2^21726814 is an apocalyptic number.

21726814 is a deficient number, since it is larger than the sum of its proper divisors (10863410).

21726814 is a wasteful number, since it uses less digits than its factorization.

21726814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10863409.

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

The square root of 21726814 is about 4661.2030635878. The cubic root of 21726814 is about 279.0392839603.

The spelling of 21726814 in words is "twenty-one million, seven hundred twenty-six thousand, eight hundred fourteen".