21126465049 has 2 divisors, whose sum is σ = 21126465050. Its totient is φ = 21126465048.

The previous prime is 21126465013. The next prime is 21126465071. The reversal of 21126465049 is 94056462112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19464435225 + 1662029824 = 139515^2 + 40768^2 .

It is a cyclic number.

It is not a de Polignac number, because 21126465049 - 2⁷ = 21126464921 is a prime.

It is not a weakly prime, because it can be changed into another prime (21126465749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10563232524 + 10563232525.

It is an arithmetic number, because the mean of its divisors is an integer number (10563232525).

Almost surely, 2^21126465049 is an apocalyptic number.

It is an amenable number.

21126465049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21126465049 is an equidigital number, since it uses as much as digits as its factorization.

21126465049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 103680, while the sum is 40.

The spelling of 21126465049 in words is "twenty-one billion, one hundred twenty-six million, four hundred sixty-five thousand, forty-nine".