21123451335024 has 120 divisors (see below), whose sum is σ = 59366676633264. Its totient is φ = 7011336960000.

The previous prime is 21123451335013. The next prime is 21123451335059. The reversal of 21123451335024 is 42053315432112.

21123451335024 is a `hidden beast` number, since 2 + 1 + 1 + 234 + 51 + 3 + 350 + 24 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 21123451335024.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 623995699 + ... + 624029549.

Almost surely, 2^{21123451335024} is an apocalyptic number.

21123451335024 is a gapful number since it is divisible by the number (24) 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 21123451335024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29683338316632).

21123451335024 is an abundant number, since it is smaller than the sum of its proper divisors (38243225298240).

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

21123451335024 is a wasteful number, since it uses less digits than its factorization.

21123451335024 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52087 (or 52078 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

Adding to 21123451335024 its reverse (42053315432112), we get a palindrome (63176766767136).

The spelling of 21123451335024 in words is "twenty-one trillion, one hundred twenty-three billion, four hundred fifty-one million, three hundred thirty-five thousand, twenty-four".