21033323123 has 4 divisors (see below), whose sum is σ = 21039317328. Its totient is φ = 21027328920.

The previous prime is 21033323119. The next prime is 21033323137. The reversal of 21033323123 is 32132333012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21033323123 - 2² = 21033323119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21033313123) 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 in 3 ways as a sum of consecutive naturals, for example, 2991836 + ... + 2998857.

It is an arithmetic number, because the mean of its divisors is an integer number (5259829332).

Almost surely, 2^21033323123 is an apocalyptic number.

21033323123 is a deficient number, since it is larger than the sum of its proper divisors (5994205).

21033323123 is an equidigital number, since it uses as much as digits as its factorization.

21033323123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5994204.

The product of its (nonzero) digits is 1944, while the sum is 23.

Adding to 21033323123 its reverse (32132333012), we get a palindrome (53165656135).

The spelling of 21033323123 in words is "twenty-one billion, thirty-three million, three hundred twenty-three thousand, one hundred twenty-three".