21031314234421 has 2 divisors, whose sum is σ = 21031314234422. Its totient is φ = 21031314234420.

The previous prime is 21031314234389. The next prime is 21031314234451. The reversal of 21031314234421 is 12443241313012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20973093370321 + 58220864100 = 4579639^2 + 241290^2 .

It is a cyclic number.

It is not a de Polignac number, because 21031314234421 - 2⁵ = 21031314234389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21031314234451) 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 as a sum of consecutive naturals, namely, 10515657117210 + 10515657117211.

It is an arithmetic number, because the mean of its divisors is an integer number (10515657117211).

Almost surely, 2^{21031314234421} is an apocalyptic number.

It is an amenable number.

21031314234421 is a deficient number, since it is larger than the sum of its proper divisors (1).

21031314234421 is an equidigital number, since it uses as much as digits as its factorization.

21031314234421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13824, while the sum is 31.

Adding to 21031314234421 its reverse (12443241313012), we get a palindrome (33474555547433).

The spelling of 21031314234421 in words is "twenty-one trillion, thirty-one billion, three hundred fourteen million, two hundred thirty-four thousand, four hundred twenty-one".