21011914789 has 2 divisors, whose sum is σ = 21011914790. Its totient is φ = 21011914788.

The previous prime is 21011914757. The next prime is 21011914801. The reversal of 21011914789 is 98741911012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17356745025 + 3655169764 = 131745^2 + 60458^2 .

It is a cyclic number.

It is not a de Polignac number, because 21011914789 - 2⁵ = 21011914757 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011914739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505957394 + 10505957395.

It is an arithmetic number, because the mean of its divisors is an integer number (10505957395).

Almost surely, 2^21011914789 is an apocalyptic number.

It is an amenable number.

21011914789 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011914789 is an equidigital number, since it uses as much as digits as its factorization.

21011914789 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 43.

The spelling of 21011914789 in words is "twenty-one billion, eleven million, nine hundred fourteen thousand, seven hundred eighty-nine".