21112078243 has 2 divisors, whose sum is σ = 21112078244. Its totient is φ = 21112078242.

The previous prime is 21112078241. The next prime is 21112078249. The reversal of 21112078243 is 34287021112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21112078243 - 2¹ = 21112078241 is a prime.

Together with 21112078241, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21112078241) 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, 10556039121 + 10556039122.

It is an arithmetic number, because the mean of its divisors is an integer number (10556039122).

Almost surely, 2^21112078243 is an apocalyptic number.

21112078243 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112078243 is an equidigital number, since it uses as much as digits as its factorization.

21112078243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 31.

Adding to 21112078243 its reverse (34287021112), we get a palindrome (55399099355).

The spelling of 21112078243 in words is "twenty-one billion, one hundred twelve million, seventy-eight thousand, two hundred forty-three".