21104012 has 12 divisors (see below), whose sum is σ = 37833096. Its totient is φ = 10294560.

The previous prime is 21104011. The next prime is 21104029. The reversal of 21104012 is 21040112.

It is a super-2 number, since 2×21104012² = 890758644992288, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21103984 and 21104002.

It is not an unprimeable number, because it can be changed into a prime (21104011) 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, 64178 + ... + 64505.

It is an arithmetic number, because the mean of its divisors is an integer number (3152758).

Almost surely, 2^21104012 is an apocalyptic number.

It is an amenable number.

21104012 is a deficient number, since it is larger than the sum of its proper divisors (16729084).

21104012 is a wasteful number, since it uses less digits than its factorization.

21104012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128728 (or 128726 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 21104012 is about 4593.9103169304. The cubic root of 21104012 is about 276.3471616895.

Adding to 21104012 its reverse (21040112), we get a palindrome (42144124).

The spelling of 21104012 in words is "twenty-one million, one hundred four thousand, twelve".