21444032461 has 2 divisors, whose sum is σ = 21444032462. Its totient is φ = 21444032460.

The previous prime is 21444032429. The next prime is 21444032483. The reversal of 21444032461 is 16423044412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11043908100 + 10400124361 = 105090^2 + 101981^2 .

It is a cyclic number.

It is not a de Polignac number, because 21444032461 - 2⁵ = 21444032429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21444012461) 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 as a sum of consecutive naturals, namely, 10722016230 + 10722016231.

It is an arithmetic number, because the mean of its divisors is an integer number (10722016231).

Almost surely, 2^21444032461 is an apocalyptic number.

It is an amenable number.

21444032461 is a deficient number, since it is larger than the sum of its proper divisors (1).

21444032461 is an equidigital number, since it uses as much as digits as its factorization.

21444032461 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18432, while the sum is 31.

Adding to 21444032461 its reverse (16423044412), we get a palindrome (37867076873).

The spelling of 21444032461 in words is "twenty-one billion, four hundred forty-four million, thirty-two thousand, four hundred sixty-one".