21055235004 has 72 divisors (see below), whose sum is σ = 54890035200. Its totient is φ = 6801151392.

The previous prime is 21055234933. The next prime is 21055235009. The reversal of 21055235004 is 40053255012.

It is a happy number.

21055235004 is a `hidden beast` number, since 2 + 105 + 52 + 3 + 500 + 4 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21055235009) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 143047 + ... + 250145.

It is an arithmetic number, because the mean of its divisors is an integer number (762361600).

Almost surely, 2^21055235004 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 21055235004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27445017600).

21055235004 is an abundant number, since it is smaller than the sum of its proper divisors (33834800196).

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

21055235004 is a wasteful number, since it uses less digits than its factorization.

21055235004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107279 (or 107274 counting only the distinct ones).

The product of its (nonzero) digits is 6000, while the sum is 27.

The spelling of 21055235004 in words is "twenty-one billion, fifty-five million, two hundred thirty-five thousand, four".