21361446829 has 2 divisors, whose sum is σ = 21361446830. Its totient is φ = 21361446828.

The previous prime is 21361446803. The next prime is 21361446853. The reversal of 21361446829 is 92864416312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17239164804 + 4122282025 = 131298^2 + 64205^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21361446829 is a prime.

It is a super-2 number, since 2×21361446829² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21361446329) 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, 10680723414 + 10680723415.

It is an arithmetic number, because the mean of its divisors is an integer number (10680723415).

Almost surely, 2^21361446829 is an apocalyptic number.

It is an amenable number.

21361446829 is a deficient number, since it is larger than the sum of its proper divisors (1).

21361446829 is an equidigital number, since it uses as much as digits as its factorization.

21361446829 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 497664, while the sum is 46.

The spelling of 21361446829 in words is "twenty-one billion, three hundred sixty-one million, four hundred forty-six thousand, eight hundred twenty-nine".