21445221042504 has 384 divisors, whose sum is σ = 70103741760000. Its totient is φ = 5912933644800.

The previous prime is 21445221042503. The next prime is 21445221042547. The reversal of 21445221042504 is 40524012254412.

21445221042504 is a `hidden beast` number, since 2 + 1 + 4 + 4 + 5 + 221 + 0 + 425 + 0 + 4 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (21445221042503) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1676580349 + ... + 1676593139.

It is an arithmetic number, because the mean of its divisors is an integer number (182561827500).

Almost surely, 2^{21445221042504} is an apocalyptic number.

21445221042504 is a gapful number since it is divisible by the number (24) 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 21445221042504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35051870880000).

21445221042504 is an abundant number, since it is smaller than the sum of its proper divisors (48658520717496).

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

21445221042504 is a wasteful number, since it uses less digits than its factorization.

21445221042504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15194 (or 15173 counting only the distinct ones).

The product of its (nonzero) digits is 102400, while the sum is 36.

Adding to 21445221042504 its reverse (40524012254412), we get a palindrome (61969233296916).

The spelling of 21445221042504 in words is "twenty-one trillion, four hundred forty-five billion, two hundred twenty-one million, forty-two thousand, five hundred four".