21214403 has 12 divisors (see below), whose sum is σ = 24753960. Its totient is φ = 18127872.

The previous prime is 21214381. The next prime is 21214429. The reversal of 21214403 is 30441212.

It is not a de Polignac number, because 21214403 - 2¹² = 21210307 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21214433) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27203 + ... + 27971.

It is an arithmetic number, because the mean of its divisors is an integer number (2062830).

Almost surely, 2^21214403 is an apocalyptic number.

21214403 is a deficient number, since it is larger than the sum of its proper divisors (3539557).

21214403 is an equidigital number, since it uses as much as digits as its factorization.

21214403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1346 (or 1339 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21214403 is about 4605.9095735804. The cubic root of 21214403 is about 276.8281634822.

Adding to 21214403 its reverse (30441212), we get a palindrome (51655615).

The spelling of 21214403 in words is "twenty-one million, two hundred fourteen thousand, four hundred three".