21431244400024 has 8 divisors (see below), whose sum is σ = 40183583250060. Its totient is φ = 10715622200008.

The previous prime is 21431244400021. The next prime is 21431244400063. The reversal of 21431244400024 is 42000444213412.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×21431244400024³ (a number of 41 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21431244400021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1339452774994 + ... + 1339452775009.

Almost surely, 2^{21431244400024} is an apocalyptic number.

It is an amenable number.

21431244400024 is a deficient number, since it is larger than the sum of its proper divisors (18752338850036).

21431244400024 is a wasteful number, since it uses less digits than its factorization.

21431244400024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2678905550009 (or 2678905550005 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 31.

Adding to 21431244400024 its reverse (42000444213412), we get a palindrome (63431688613436).

The spelling of 21431244400024 in words is "twenty-one trillion, four hundred thirty-one billion, two hundred forty-four million, four hundred thousand, twenty-four".