21115344431423 has 8 divisors (see below), whose sum is σ = 23570617040256. Its totient is φ = 18749354463000.

The previous prime is 21115344431399. The next prime is 21115344431437. The reversal of 21115344431423 is 32413444351112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21115344431423 - 2¹⁶ = 21115344365887 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115344431023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22320659603 + ... + 22320660548.

It is an arithmetic number, because the mean of its divisors is an integer number (2946327130032).

Almost surely, 2^{21115344431423} is an apocalyptic number.

21115344431423 is a deficient number, since it is larger than the sum of its proper divisors (2455272608833).

21115344431423 is a wasteful number, since it uses less digits than its factorization.

21115344431423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44641320205.

The product of its digits is 138240, while the sum is 38.

Adding to 21115344431423 its reverse (32413444351112), we get a palindrome (53528788782535).

The spelling of 21115344431423 in words is "twenty-one trillion, one hundred fifteen billion, three hundred forty-four million, four hundred thirty-one thousand, four hundred twenty-three".