21022207 has 8 divisors (see below), whose sum is σ = 22404096. Its totient is φ = 19679352.

The previous prime is 21022193. The next prime is 21022213. The reversal of 21022207 is 70222012.

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

It is not a de Polignac number, because 21022207 - 2¹¹ = 21020159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21022277) 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, 8643 + ... + 10804.

It is an arithmetic number, because the mean of its divisors is an integer number (2800512).

Almost surely, 2^21022207 is an apocalyptic number.

21022207 is a deficient number, since it is larger than the sum of its proper divisors (1381889).

21022207 is a wasteful number, since it uses less digits than its factorization.

21022207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19517.

The product of its (nonzero) digits is 112, while the sum is 16.

The square root of 21022207 is about 4584.9980370770. The cubic root of 21022207 is about 275.9896332660.

Adding to 21022207 its reverse (70222012), we get a palindrome (91244219).

The spelling of 21022207 in words is "twenty-one million, twenty-two thousand, two hundred seven".