21330124441421 has 4 divisors (see below), whose sum is σ = 21330150524352. Its totient is φ = 21330098358492.

The previous prime is 21330124441399. The next prime is 21330124441517. The reversal of 21330124441421 is 12414442103312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21330124441421 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 (21330124441621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11773715 + ... + 13464048.

It is an arithmetic number, because the mean of its divisors is an integer number (5332537631088).

Almost surely, 2^{21330124441421} is an apocalyptic number.

It is an amenable number.

21330124441421 is a deficient number, since it is larger than the sum of its proper divisors (26082931).

21330124441421 is an equidigital number, since it uses as much as digits as its factorization.

21330124441421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26082930.

The product of its (nonzero) digits is 18432, while the sum is 32.

Adding to 21330124441421 its reverse (12414442103312), we get a palindrome (33744566544733).

The spelling of 21330124441421 in words is "twenty-one trillion, three hundred thirty billion, one hundred twenty-four million, four hundred forty-one thousand, four hundred twenty-one".