21532421042421 has 8 divisors (see below), whose sum is σ = 28710032823360. Its totient is φ = 14354878311552.

The previous prime is 21532421042411. The next prime is 21532421042477. The reversal of 21532421042421 is 12424012423512.

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

It is not a de Polignac number, because 21532421042421 - 2¹¹ = 21532421040373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21532421042411) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 16530460 + ... + 17785413.

It is an arithmetic number, because the mean of its divisors is an integer number (3588754102920).

Almost surely, 2^{21532421042421} is an apocalyptic number.

It is an amenable number.

21532421042421 is a deficient number, since it is larger than the sum of its proper divisors (7177611780939).

21532421042421 is a wasteful number, since it uses less digits than its factorization.

21532421042421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34525035.

The product of its (nonzero) digits is 30720, while the sum is 33.

Adding to 21532421042421 its reverse (12424012423512), we get a palindrome (33956433465933).

The spelling of 21532421042421 in words is "twenty-one trillion, five hundred thirty-two billion, four hundred twenty-one million, forty-two thousand, four hundred twenty-one".