212121111000000 has 1568 divisors, whose sum is σ = 791574517716480. Its totient is φ = 49861785600000.

The previous prime is 212121110999983. The next prime is 212121111000047. The reversal of 212121111000000 is 111121212.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a self number, because there is not a number n which added to its sum of digits gives 212121111000000.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 48506997814 + ... + 48507002186.

Almost surely, 2^{212121111000000} is an apocalyptic number.

212121111000000 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 212121111000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (395787258858240).

212121111000000 is an abundant number, since it is smaller than the sum of its proper divisors (579453406716480).

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

212121111000000 is an equidigital number, since it uses as much as digits as its factorization.

212121111000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4497 (or 4462 counting only the distinct ones).

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

Adding to 212121111000000 its reverse (111121212), we get a palindrome (212121222121212).

The spelling of 212121111000000 in words is "two hundred twelve trillion, one hundred twenty-one billion, one hundred eleven million", and thus it is an aban number.