21144112423 has 16 divisors (see below), whose sum is σ = 25602018624. Its totient is φ = 17046858240.

The previous prime is 21144112411. The next prime is 21144112439. The reversal of 21144112423 is 32421144112.

It is a cyclic number.

It is not a de Polignac number, because 21144112423 - 2²⁹ = 20607241511 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21144112723) 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 in 15 ways as a sum of consecutive naturals, for example, 140533 + ... + 249073.

It is an arithmetic number, because the mean of its divisors is an integer number (1600126164).

Almost surely, 2^21144112423 is an apocalyptic number.

21144112423 is a deficient number, since it is larger than the sum of its proper divisors (4457906201).

21144112423 is a wasteful number, since it uses less digits than its factorization.

21144112423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110202.

The product of its digits is 1536, while the sum is 25.

Adding to 21144112423 its reverse (32421144112), we get a palindrome (53565256535).

The spelling of 21144112423 in words is "twenty-one billion, one hundred forty-four million, one hundred twelve thousand, four hundred twenty-three".