21123013434323 has 16 divisors (see below), whose sum is σ = 22500324957600. Its totient is φ = 19760733820416.

The previous prime is 21123013434307. The next prime is 21123013434337. The reversal of 21123013434323 is 32343431032112.

It is a cyclic number.

It is not a de Polignac number, because 21123013434323 - 2⁴ = 21123013434307 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21123013434323.

It is not an unprimeable number, because it can be changed into a prime (21123013434823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11179061 + ... + 12931257.

It is an arithmetic number, because the mean of its divisors is an integer number (1406270309850).

Almost surely, 2^{21123013434323} is an apocalyptic number.

21123013434323 is a deficient number, since it is larger than the sum of its proper divisors (1377311523277).

21123013434323 is a wasteful number, since it uses less digits than its factorization.

21123013434323 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1756486.

The product of its (nonzero) digits is 31104, while the sum is 32.

Adding to 21123013434323 its reverse (32343431032112), we get a palindrome (53466444466435).

The spelling of 21123013434323 in words is "twenty-one trillion, one hundred twenty-three billion, thirteen million, four hundred thirty-four thousand, three hundred twenty-three".