21822215 has 8 divisors (see below), whose sum is σ = 26354400. Its totient is φ = 17345952.

The previous prime is 21822197. The next prime is 21822217. The reversal of 21822215 is 51222812.

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

It is a cyclic number.

It is not a de Polignac number, because 21822215 - 2¹² = 21818119 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21822217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13115 + ... + 14684.

It is an arithmetic number, because the mean of its divisors is an integer number (3294300).

Almost surely, 2^21822215 is an apocalyptic number.

21822215 is a deficient number, since it is larger than the sum of its proper divisors (4532185).

21822215 is a wasteful number, since it uses less digits than its factorization.

21822215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27961.

The product of its digits is 640, while the sum is 23.

The square root of 21822215 is about 4671.4253713401. The cubic root of 21822215 is about 279.4471019736.

The spelling of 21822215 in words is "twenty-one million, eight hundred twenty-two thousand, two hundred fifteen".