21208414 has 4 divisors (see below), whose sum is σ = 31812624. Its totient is φ = 10604206.

The previous prime is 21208399. The next prime is 21208423. The reversal of 21208414 is 41480212.

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

It is a Smith number, since the sum of its digits (22) 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 polite number, since it can be written as a sum of consecutive naturals, namely, 5302102 + ... + 5302105.

It is an arithmetic number, because the mean of its divisors is an integer number (7953156).

Almost surely, 2^21208414 is an apocalyptic number.

21208414 is a deficient number, since it is larger than the sum of its proper divisors (10604210).

21208414 is a wasteful number, since it uses less digits than its factorization.

21208414 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10604209.

The product of its (nonzero) digits is 512, while the sum is 22.

The square root of 21208414 is about 4605.2593846601. The cubic root of 21208414 is about 276.8021107433.

Adding to 21208414 its reverse (41480212), we get a palindrome (62688626).

The spelling of 21208414 in words is "twenty-one million, two hundred eight thousand, four hundred fourteen".