21442021552520 has 64 divisors (see below), whose sum is σ = 48430590692400. Its totient is φ = 8543796940800.

The previous prime is 21442021552499. The next prime is 21442021552619. The reversal of 21442021552520 is 2525512024412.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 21308397674404 + 133623878116 = 4616102^2 + 365546^2 .

It is a super-2 number, since 2×21442021552520² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10010426 + ... + 11962134.

Almost surely, 2^{21442021552520} is an apocalyptic number.

21442021552520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21442021552520 is an abundant number, since it is smaller than the sum of its proper divisors (26988569139880).

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

21442021552520 is a wasteful number, since it uses less digits than its factorization.

21442021552520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1952778 (or 1952774 counting only the distinct ones).

The product of its (nonzero) digits is 64000, while the sum is 35.

Adding to 21442021552520 its reverse (2525512024412), we get a palindrome (23967533576932).

The spelling of 21442021552520 in words is "twenty-one trillion, four hundred forty-two billion, twenty-one million, five hundred fifty-two thousand, five hundred twenty".