21552440531021 has 8 divisors (see below), whose sum is σ = 21564069612864. Its totient is φ = 21540812388480.

The previous prime is 21552440530991. The next prime is 21552440531029. The reversal of 21552440531021 is 12013504425512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21552440531021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21552440531029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48369776 + ... + 48813318.

It is an arithmetic number, because the mean of its divisors is an integer number (2695508701608).

Almost surely, 2^{21552440531021} is an apocalyptic number.

It is an amenable number.

21552440531021 is a deficient number, since it is larger than the sum of its proper divisors (11629081843).

21552440531021 is a wasteful number, since it uses less digits than its factorization.

21552440531021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469651.

The product of its (nonzero) digits is 48000, while the sum is 35.

Adding to 21552440531021 its reverse (12013504425512), we get a palindrome (33565944956533).

The spelling of 21552440531021 in words is "twenty-one trillion, five hundred fifty-two billion, four hundred forty million, five hundred thirty-one thousand, twenty-one".