21011212122000 has 320 divisors, whose sum is σ = 68856040431360. Its totient is φ = 5511281664000.

The previous prime is 21011212121993. The next prime is 21011212122007. The reversal of 21011212122000 is 22121211012.

It is an interprime number because it is at equal distance from previous prime (21011212121993) and next prime (21011212122007).

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

It is not an unprimeable number, because it can be changed into a prime (21011212122007) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 113949880 + ... + 114134120.

It is an arithmetic number, because the mean of its divisors is an integer number (215175126348).

Almost surely, 2^{21011212122000} is an apocalyptic number.

21011212122000 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 21011212122000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34428020215680).

21011212122000 is an abundant number, since it is smaller than the sum of its proper divisors (47844828309360).

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

21011212122000 is a wasteful number, since it uses less digits than its factorization.

21011212122000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184579 (or 184563 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21011212122000 its reverse (22121211012), we get a palindrome (21033333333012).

The spelling of 21011212122000 in words is "twenty-one trillion, eleven billion, two hundred twelve million, one hundred twenty-two thousand".