21121450289 has 2 divisors, whose sum is σ = 21121450290. Its totient is φ = 21121450288.

The previous prime is 21121450283. The next prime is 21121450319. The reversal of 21121450289 is 98205412112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15200917264 + 5920533025 = 123292^2 + 76945^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21121450289 is a prime.

It is a super-2 number, since 2×21121450289² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21121450283) 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, 10560725144 + 10560725145.

It is an arithmetic number, because the mean of its divisors is an integer number (10560725145).

Almost surely, 2^21121450289 is an apocalyptic number.

It is an amenable number.

21121450289 is a deficient number, since it is larger than the sum of its proper divisors (1).

21121450289 is an equidigital number, since it uses as much as digits as its factorization.

21121450289 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11520, while the sum is 35.

The spelling of 21121450289 in words is "twenty-one billion, one hundred twenty-one million, four hundred fifty thousand, two hundred eighty-nine".