1021541220000 has 1800 divisors, whose sum is σ = 4630133573604. Its totient is φ = 219469824000.

The previous prime is 1021541219989. The next prime is 1021541220023. The reversal of 1021541220000 is 221451201.

1021541220000 is a `hidden beast` number, since 102 + 1 + 541 + 2 + 20 + 0 + 0 + 0 = 666.

It can be written as a sum of positive squares in 10 ways, for example, as 5985188496 + 1015556031504 = 77364^2 + 1007748^2 .

It is a tau number, because it is divible by the number of its divisors (1800).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 299 ways as a sum of consecutive naturals, for example, 1349459622 + ... + 1349460378.

Almost surely, 2^{1021541220000} is an apocalyptic number.

1021541220000 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 1021541220000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2315066786802).

1021541220000 is an abundant number, since it is smaller than the sum of its proper divisors (3608592353604).

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

1021541220000 is an equidigital number, since it uses as much as digits as its factorization.

1021541220000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 830 (or 791 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

Adding to 1021541220000 its reverse (221451201), we get a palindrome (1021762671201).

The spelling of 1021541220000 in words is "one trillion, twenty-one billion, five hundred forty-one million, two hundred twenty thousand".