21238484681 has 4 divisors (see below), whose sum is σ = 21242717952. Its totient is φ = 21234251412.

The previous prime is 21238484633. The next prime is 21238484723. The reversal of 21238484681 is 18648483212.

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 not a de Polignac number, because 21238484681 - 2³⁴ = 4058615497 is a prime.

It is a super-2 number, since 2×21238484681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21238484881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2109101 + ... + 2119146.

It is an arithmetic number, because the mean of its divisors is an integer number (5310679488).

Almost surely, 2^21238484681 is an apocalyptic number.

It is an amenable number.

21238484681 is a deficient number, since it is larger than the sum of its proper divisors (4233271).

21238484681 is an equidigital number, since it uses as much as digits as its factorization.

21238484681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4233270.

The product of its digits is 589824, while the sum is 47.

The spelling of 21238484681 in words is "twenty-one billion, two hundred thirty-eight million, four hundred eighty-four thousand, six hundred eighty-one".