21107229 has 16 divisors (see below), whose sum is σ = 33063744. Its totient is φ = 11808000.

The previous prime is 21107227. The next prime is 21107239. The reversal of 21107229 is 92270112.

It is not a de Polignac number, because 21107229 - 2¹ = 21107227 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21107199 and 21107208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21107221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24172 + ... + 25029.

It is an arithmetic number, because the mean of its divisors is an integer number (2066484).

Almost surely, 2^21107229 is an apocalyptic number.

It is an amenable number.

21107229 is a deficient number, since it is larger than the sum of its proper divisors (11956515).

21107229 is a wasteful number, since it uses less digits than its factorization.

21107229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49228.

The product of its (nonzero) digits is 504, while the sum is 24.

The square root of 21107229 is about 4594.2604410286. The cubic root of 21107229 is about 276.3612026793.

It can be divided in two parts, 2110 and 7229, that added together give a palindrome (9339).

The spelling of 21107229 in words is "twenty-one million, one hundred seven thousand, two hundred twenty-nine".