21242103545520 has 800 divisors, whose sum is σ = 86837306681664. Its totient is φ = 4744579276800.

The previous prime is 21242103545501. The next prime is 21242103545567. The reversal of 21242103545520 is 2554530124212.

21242103545520 is a `hidden beast` number, since 2 + 1 + 2 + 4 + 2 + 103 + 545 + 5 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 501291054 + ... + 501333426.

Almost surely, 2^{21242103545520} is an apocalyptic number.

21242103545520 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 21242103545520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43418653340832).

21242103545520 is an abundant number, since it is smaller than the sum of its proper divisors (65595203136144).

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

21242103545520 is a wasteful number, since it uses less digits than its factorization.

21242103545520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42963 (or 42948 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 36.

Adding to 21242103545520 its reverse (2554530124212), we get a palindrome (23796633669732).

The spelling of 21242103545520 in words is "twenty-one trillion, two hundred forty-two billion, one hundred three million, five hundred forty-five thousand, five hundred twenty".