12210021000 has 288 divisors, whose sum is σ = 42878024280. Its totient is φ = 3254256000.

The previous prime is 12210020941. The next prime is 12210021013. The reversal of 12210021000 is 12001221.

It can be written as a sum of positive squares in 4 ways, for example, as 464230116 + 11745790884 = 21546^2 + 108378^2 .

It is a super-2 number, since 2×12210021000² (a number of 21 digits) contains 22 as substring.

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

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 6560070 + ... + 6561930.

Almost surely, 2^12210021000 is an apocalyptic number.

12210021000 is a gapful number since it is divisible by the number (10) 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 12210021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21439012140).

12210021000 is an abundant number, since it is smaller than the sum of its proper divisors (30668003280).

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

12210021000 is an frugal number, since it uses more digits than its factorization.

12210021000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1906 (or 1871 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 12210021000 its reverse (12001221), we get a palindrome (12222022221).

The spelling of 12210021000 in words is "twelve billion, two hundred ten million, twenty-one thousand".