21033220279 has 2 divisors, whose sum is σ = 21033220280. Its totient is φ = 21033220278.

The previous prime is 21033220277. The next prime is 21033220333. The reversal of 21033220279 is 97202233012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21033220279 - 2¹ = 21033220277 is a prime.

Together with 21033220277, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21033220279.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21033220277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516610139 + 10516610140.

It is an arithmetic number, because the mean of its divisors is an integer number (10516610140).

Almost surely, 2^21033220279 is an apocalyptic number.

21033220279 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033220279 is an equidigital number, since it uses as much as digits as its factorization.

21033220279 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9072, while the sum is 31.

The spelling of 21033220279 in words is "twenty-one billion, thirty-three million, two hundred twenty thousand, two hundred seventy-nine".