21030404 has 12 divisors (see below), whose sum is σ = 36841728. Its totient is φ = 10504200.

The previous prime is 21030403. The next prime is 21030463. The reversal of 21030404 is 40403012.

It is not an unprimeable number, because it can be changed into a prime (21030403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2789 + ... + 7059.

It is an arithmetic number, because the mean of its divisors is an integer number (3070144).

Almost surely, 2^21030404 is an apocalyptic number.

It is an amenable number.

21030404 is a deficient number, since it is larger than the sum of its proper divisors (15811324).

21030404 is a wasteful number, since it uses less digits than its factorization.

21030404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5506 (or 5504 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 21030404 is about 4585.8918434695. The cubic root of 21030404 is about 276.0254999894.

Adding to 21030404 its reverse (40403012), we get a palindrome (61433416).

The spelling of 21030404 in words is "twenty-one million, thirty thousand, four hundred four".