1521221203320 has 1024 divisors, whose sum is σ = 5955489792000. Its totient is φ = 308558315520.

The previous prime is 1521221203261. The next prime is 1521221203399. The reversal of 1521221203320 is 233021221251.

It is a super-2 number, since 2×1521221203320² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

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 255 ways as a sum of consecutive naturals, for example, 4860131484 + ... + 4860131796.

It is an arithmetic number, because the mean of its divisors is an integer number (5815908000).

Almost surely, 2^{1521221203320} is an apocalyptic number.

1521221203320 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 1521221203320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2977744896000).

1521221203320 is an abundant number, since it is smaller than the sum of its proper divisors (4434268588680).

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

1521221203320 is a wasteful number, since it uses less digits than its factorization.

1521221203320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 685 (or 667 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

Adding to 1521221203320 its reverse (233021221251), we get a palindrome (1754242424571).

The spelling of 1521221203320 in words is "one trillion, five hundred twenty-one billion, two hundred twenty-one million, two hundred three thousand, three hundred twenty".