21909214 has 8 divisors (see below), whose sum is σ = 32903928. Its totient is φ = 10941240.

The previous prime is 21909169. The next prime is 21909227. The reversal of 21909214 is 41290912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4492 + ... + 7999.

It is an arithmetic number, because the mean of its divisors is an integer number (4112991).

Almost surely, 2^21909214 is an apocalyptic number.

21909214 is a deficient number, since it is larger than the sum of its proper divisors (10994714).

21909214 is a wasteful number, since it uses less digits than its factorization.

21909214 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13370.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 21909214 is about 4680.7279348409. The cubic root of 21909214 is about 279.8179684193.

The spelling of 21909214 in words is "twenty-one million, nine hundred nine thousand, two hundred fourteen".