21130404 has 24 divisors (see below), whose sum is σ = 50637888. Its totient is φ = 6852960.

The previous prime is 21130397. The next prime is 21130409. The reversal of 21130404 is 40403112.

It is not an unprimeable number, because it can be changed into a prime (21130409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23352 + ... + 24239.

It is an arithmetic number, because the mean of its divisors is an integer number (2109912).

Almost surely, 2^21130404 is an apocalyptic number.

It is an amenable number.

21130404 is an abundant number, since it is smaller than the sum of its proper divisors (29507484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21130404 is a wasteful number, since it uses less digits than its factorization.

21130404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47635 (or 47633 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21130404 is about 4596.7819178203. The cubic root of 21130404 is about 276.4623106656.

Adding to 21130404 its reverse (40403112), we get a palindrome (61533516).

The spelling of 21130404 in words is "twenty-one million, one hundred thirty thousand, four hundred four".