21114215 has 4 divisors (see below), whose sum is σ = 25337064. Its totient is φ = 16891368.

The previous prime is 21114211. The next prime is 21114217. The reversal of 21114215 is 51241112.

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

It is a cyclic number.

It is not a de Polignac number, because 21114215 - 2² = 21114211 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21114193 and 21114202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21114211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2111417 + ... + 2111426.

It is an arithmetic number, because the mean of its divisors is an integer number (6334266).

Almost surely, 2^21114215 is an apocalyptic number.

21114215 is a deficient number, since it is larger than the sum of its proper divisors (4222849).

21114215 is an equidigital number, since it uses as much as digits as its factorization.

21114215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4222848.

The product of its digits is 80, while the sum is 17.

The square root of 21114215 is about 4595.0206745998. The cubic root of 21114215 is about 276.3916890180.

Adding to 21114215 its reverse (51241112), we get a palindrome (72355327).

The spelling of 21114215 in words is "twenty-one million, one hundred fourteen thousand, two hundred fifteen".