21078214 has 8 divisors (see below), whose sum is σ = 31694040. Its totient is φ = 10513536.

The previous prime is 21078209. The next prime is 21078257. The reversal of 21078214 is 41287012.

It is a happy number.

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

It is a super-2 number, since 2×21078214² = 888582210859592, which contains 22 as substring.

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, 11739 + ... + 13414.

It is an arithmetic number, because the mean of its divisors is an integer number (3961755).

Almost surely, 2^21078214 is an apocalyptic number.

21078214 is a deficient number, since it is larger than the sum of its proper divisors (10615826).

21078214 is a wasteful number, since it uses less digits than its factorization.

21078214 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25574.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 21078214 is about 4591.1016107248. The cubic root of 21078214 is about 276.2345115290.

The spelling of 21078214 in words is "twenty-one million, seventy-eight thousand, two hundred fourteen".