21000123330 has 96 divisors (see below), whose sum is σ = 52027363584. Its totient is φ = 5421600000.

The previous prime is 21000123329. The next prime is 21000123383. The reversal of 21000123330 is 3332100012.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 77491095 + ... + 77491365.

It is an arithmetic number, because the mean of its divisors is an integer number (541951704).

Almost surely, 2^21000123330 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21000123330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26013681792).

21000123330 is an abundant number, since it is smaller than the sum of its proper divisors (31027240254).

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

21000123330 is a wasteful number, since it uses less digits than its factorization.

21000123330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 824 (or 573 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 15.

Adding to 21000123330 its reverse (3332100012), we get a palindrome (24332223342).

The spelling of 21000123330 in words is "twenty-one billion, one hundred twenty-three thousand, three hundred thirty".