21002233123 has 2 divisors, whose sum is σ = 21002233124. Its totient is φ = 21002233122.

The previous prime is 21002233117. The next prime is 21002233139. The reversal of 21002233123 is 32133220012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21002233123 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21002233123.

It is not a weakly prime, because it can be changed into another prime (21002233163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10501116561 + 10501116562.

It is an arithmetic number, because the mean of its divisors is an integer number (10501116562).

Almost surely, 2^21002233123 is an apocalyptic number.

21002233123 is a deficient number, since it is larger than the sum of its proper divisors (1).

21002233123 is an equidigital number, since it uses as much as digits as its factorization.

21002233123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21002233123 its reverse (32133220012), we get a palindrome (53135453135).

The spelling of 21002233123 in words is "twenty-one billion, two million, two hundred thirty-three thousand, one hundred twenty-three".