21312430004400 has 240 divisors, whose sum is σ = 72310408159104. Its totient is φ = 5347251261440.

The previous prime is 21312430004389. The next prime is 21312430004473. The reversal of 21312430004400 is 440003421312.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 62723767 + ... + 63062633.

Almost surely, 2^{21312430004400} is an apocalyptic number.

21312430004400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21312430004400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36155204079552).

21312430004400 is an abundant number, since it is smaller than the sum of its proper divisors (50997978154704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21312430004400 is a wasteful number, since it uses less digits than its factorization.

21312430004400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341988 (or 341977 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 24.

Adding to 21312430004400 its reverse (440003421312), we get a palindrome (21752433425712).

The spelling of 21312430004400 in words is "twenty-one trillion, three hundred twelve billion, four hundred thirty million, four thousand, four hundred".