21012334421 has 8 divisors (see below), whose sum is σ = 22647339960. Its totient is φ = 19379996352.

The previous prime is 21012334379. The next prime is 21012334423. The reversal of 21012334421 is 12443321012.

It can be written as a sum of positive squares in 4 ways, for example, as 720331921 + 20292002500 = 26839^2 + 142450^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 21012334421 - 2²² = 21008140117 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 (21012334423) 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 7 ways as a sum of consecutive naturals, for example, 650486 + ... + 682023.

It is an arithmetic number, because the mean of its divisors is an integer number (2830917495).

Almost surely, 2^21012334421 is an apocalyptic number.

It is an amenable number.

21012334421 is a deficient number, since it is larger than the sum of its proper divisors (1635005539).

21012334421 is a wasteful number, since it uses less digits than its factorization.

21012334421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1333735.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21012334421 its reverse (12443321012), we get a palindrome (33455655433).

The spelling of 21012334421 in words is "twenty-one billion, twelve million, three hundred thirty-four thousand, four hundred twenty-one".