21041109 has 6 divisors (see below), whose sum is σ = 30392726. Its totient is φ = 14027400.

The previous prime is 21041107. The next prime is 21041117. The reversal of 21041109 is 90114012.

It can be written as a sum of positive squares in only one way, i.e., 17514225 + 3526884 = 4185^2 + 1878^2 .

It is not a de Polignac number, because 21041109 - 2¹ = 21041107 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21041091 and 21041100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21041107) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1168942 + ... + 1168959.

Almost surely, 2^21041109 is an apocalyptic number.

It is an amenable number.

21041109 is a deficient number, since it is larger than the sum of its proper divisors (9351617).

21041109 is a wasteful number, since it uses less digits than its factorization.

21041109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2337907 (or 2337904 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 21041109 is about 4587.0588616236. The cubic root of 21041109 is about 276.0723266656.

The spelling of 21041109 in words is "twenty-one million, forty-one thousand, one hundred nine".