21123104321124 has 144 divisors (see below), whose sum is σ = 58376369425920. Its totient is φ = 6400977073920.

The previous prime is 21123104321107. The next prime is 21123104321131. The reversal of 21123104321124 is 42112340132112.

21123104321124 is a `hidden beast` number, since 2 + 1 + 1 + 2 + 310 + 4 + 321 + 1 + 24 = 666.

It is a super-2 number, since 2×21123104321124² (a number of 27 digits) contains 22 as substring.

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, 13958329 + ... + 15397439.

Almost surely, 2^{21123104321124} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21123104321124, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29188184712960).

21123104321124 is an abundant number, since it is smaller than the sum of its proper divisors (37253265104796).

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

21123104321124 is a wasteful number, since it uses less digits than its factorization.

21123104321124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1439610 (or 1439605 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 27.

Adding to 21123104321124 its reverse (42112340132112), we get a palindrome (63235444453236).

The spelling of 21123104321124 in words is "twenty-one trillion, one hundred twenty-three billion, one hundred four million, three hundred twenty-one thousand, one hundred twenty-four".