21000230000 has 100 divisors (see below), whose sum is σ = 50913989808. Its totient is φ = 8388480000.

The previous prime is 21000229993. The next prime is 21000230003. The reversal of 21000230000 is 3200012.

It is a tau number, because it is divible by the number of its divisors (100).

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a self number, because there is not a number n which added to its sum of digits gives 21000230000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000230003) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 13609229 + ... + 13610771.

Almost surely, 2^21000230000 is an apocalyptic number.

21000230000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21000230000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25456994904).

21000230000 is an abundant number, since it is smaller than the sum of its proper divisors (29913759808).

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

21000230000 is a wasteful number, since it uses less digits than its factorization.

21000230000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2932 (or 2911 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 8.

Adding to 21000230000 its reverse (3200012), we get a palindrome (21003430012).

The spelling of 21000230000 in words is "twenty-one billion, two hundred thirty thousand".