21042004992 has 88 divisors (see below), whose sum is σ = 56922255456. Its totient is φ = 6909247488.

The previous prime is 21042004981. The next prime is 21042004999. The reversal of 21042004992 is 29940024012.

It is not an unprimeable number, because it can be changed into a prime (21042004999) 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, 154708 + ... + 256940.

It is an arithmetic number, because the mean of its divisors is an integer number (646843812).

Almost surely, 2^21042004992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21042004992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28461127728).

21042004992 is an abundant number, since it is smaller than the sum of its proper divisors (35880250464).

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

21042004992 is a wasteful number, since it uses less digits than its factorization.

21042004992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102323 (or 102305 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The spelling of 21042004992 in words is "twenty-one billion, forty-two million, four thousand, nine hundred ninety-two".