21002013000 has 384 divisors, whose sum is σ = 75169036800. Its totient is φ = 5277888000.

The previous prime is 21002012971. The next prime is 21002013007. The reversal of 21002013000 is 31020012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21002013007) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 14696286 + ... + 14697714.

It is an arithmetic number, because the mean of its divisors is an integer number (195752700).

Almost surely, 2^21002013000 is an apocalyptic number.

21002013000 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 21002013000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37584518400).

21002013000 is an abundant number, since it is smaller than the sum of its proper divisors (54167023800).

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

21002013000 is a wasteful number, since it uses less digits than its factorization.

21002013000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1550 (or 1533 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

Adding to 21002013000 its reverse (31020012), we get a palindrome (21033033012).

The spelling of 21002013000 in words is "twenty-one billion, two million, thirteen thousand".