21011104 has 12 divisors (see below), whose sum is σ = 41365674. Its totient is φ = 10505536.

The previous prime is 21011083. The next prime is 21011141. The reversal of 21011104 is 40111012.

It can be written as a sum of positive squares in only one way, i.e., 11696400 + 9314704 = 3420^2 + 3052^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328267 + ... + 328330.

Almost surely, 2^21011104 is an apocalyptic number.

It is an amenable number.

21011104 is a deficient number, since it is larger than the sum of its proper divisors (20354570).

21011104 is an equidigital number, since it uses as much as digits as its factorization.

21011104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656607 (or 656599 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 21011104 is about 4583.7870805700. The cubic root of 21011104 is about 275.9410362033.

Adding to 21011104 its reverse (40111012), we get a palindrome (61122116).

It can be divided in two parts, 21011 and 104, that added together give a triangular number (21115 = T₂₀₅).

The spelling of 21011104 in words is "twenty-one million, eleven thousand, one hundred four".