21109627 has 32 divisors (see below), whose sum is σ = 28385280. Its totient is φ = 15202080.

The previous prime is 21109591. The next prime is 21109637. The reversal of 21109627 is 72690112.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21109627 - 2²³ = 12721019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21109595 and 21109604.

It is not an unprimeable number, because it can be changed into a prime (21109637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 68608 + ... + 68914.

It is an arithmetic number, because the mean of its divisors is an integer number (887040).

Almost surely, 2^21109627 is an apocalyptic number.

21109627 is a deficient number, since it is larger than the sum of its proper divisors (7275653).

21109627 is a wasteful number, since it uses less digits than its factorization.

21109627 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 21109627 is about 4594.5214114203. The cubic root of 21109627 is about 276.3716681154.

Adding to 21109627 its reverse (72690112), we get a palindrome (93799739).

It can be divided in two parts, 21109 and 627, that added together give a triangular number (21736 = T₂₀₈).

The spelling of 21109627 in words is "twenty-one million, one hundred nine thousand, six hundred twenty-seven".