21130104 has 16 divisors (see below), whose sum is σ = 52825320. Its totient is φ = 7043360.

The previous prime is 21130079. The next prime is 21130111. The reversal of 21130104 is 40103112.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a self number, because there is not a number n which added to its sum of digits gives 21130104.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 440187 + ... + 440234.

Almost surely, 2^21130104 is an apocalyptic number.

21130104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21130104 is an abundant number, since it is smaller than the sum of its proper divisors (31695216).

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

21130104 is a wasteful number, since it uses less digits than its factorization.

21130104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 880430 (or 880426 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21130104 is about 4596.7492861804. The cubic root of 21130104 is about 276.4610022968.

Adding to 21130104 its reverse (40103112), we get a palindrome (61233216).

The spelling of 21130104 in words is "twenty-one million, one hundred thirty thousand, one hundred four".