21412215 has 32 divisors (see below), whose sum is σ = 41529600. Its totient is φ = 10380960.

The previous prime is 21412189. The next prime is 21412217. The reversal of 21412215 is 51221412.

It is not a de Polignac number, because 21412215 - 2¹⁴ = 21395831 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21412217) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5725 + ... + 8694.

It is an arithmetic number, because the mean of its divisors is an integer number (1297800).

Almost surely, 2^21412215 is an apocalyptic number.

21412215 is a deficient number, since it is larger than the sum of its proper divisors (20117385).

21412215 is a wasteful number, since it uses less digits than its factorization.

21412215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14444 (or 14438 counting only the distinct ones).

The product of its digits is 160, while the sum is 18.

The square root of 21412215 is about 4627.3334653988. Note that the first 3 decimals coincide. The cubic root of 21412215 is about 277.6859236147.

Adding to 21412215 its reverse (51221412), we get a palindrome (72633627).

It can be divided in two parts, 2141 and 2215, that added together give a square (4356 = 66²).

The spelling of 21412215 in words is "twenty-one million, four hundred twelve thousand, two hundred fifteen".