21039104 has 24 divisors (see below), whose sum is σ = 42072030. Its totient is φ = 10518528.

The previous prime is 21039103. The next prime is 21039107. The reversal of 21039104 is 40193012.

It can be written as a sum of positive squares in only one way, i.e., 19784704 + 1254400 = 4448^2 + 1120^2 .

It is not an unprimeable number, because it can be changed into a prime (21039101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3089 + ... + 7184.

Almost surely, 2^21039104 is an apocalyptic number.

It is an amenable number.

21039104 is a deficient number, since it is larger than the sum of its proper divisors (21032926).

21039104 is an equidigital number, since it uses as much as digits as its factorization.

21039104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10295 (or 10275 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 21039104 is about 4586.8403067907. The cubic root of 21039104 is about 276.0635574415.

The spelling of 21039104 in words is "twenty-one million, thirty-nine thousand, one hundred four".