21013204104 has 48 divisors (see below), whose sum is σ = 57760188720. Its totient is φ = 6899856480.

The previous prime is 21013204073. The next prime is 21013204111. The reversal of 21013204104 is 40140231012.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2173162 + ... + 2182809.

It is an arithmetic number, because the mean of its divisors is an integer number (1203337265).

Almost surely, 2^21013204104 is an apocalyptic number.

21013204104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21013204104 is an abundant number, since it is smaller than the sum of its proper divisors (36746984616).

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

21013204104 is a wasteful number, since it uses less digits than its factorization.

21013204104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4356050 (or 4356043 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21013204104 its reverse (40140231012), we get a palindrome (61153435116).

The spelling of 21013204104 in words is "twenty-one billion, thirteen million, two hundred four thousand, one hundred four".