21244023423 has 12 divisors (see below), whose sum is σ = 35069499088. Its totient is φ = 12139441920.

The previous prime is 21244023403. The next prime is 21244023473. The reversal of 21244023423 is 32432044212.

21244023423 is a `hidden beast` number, since 212 + 4 + 4 + 0 + 23 + 423 = 666.

It is not a de Polignac number, because 21244023423 - 2¹⁰ = 21244022399 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21244023403) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 168603298 + ... + 168603423.

Almost surely, 2^21244023423 is an apocalyptic number.

21244023423 is a deficient number, since it is larger than the sum of its proper divisors (13825475665).

21244023423 is a wasteful number, since it uses less digits than its factorization.

21244023423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 337206734 (or 337206731 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21244023423 its reverse (32432044212), we get a palindrome (53676067635).

The spelling of 21244023423 in words is "twenty-one billion, two hundred forty-four million, twenty-three thousand, four hundred twenty-three".