21123100312000 has 112 divisors (see below), whose sum is σ = 52363018049472. Its totient is φ = 8440896076800.

The previous prime is 21123100311983. The next prime is 21123100312001. The reversal of 21123100312000 is 21300132112.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123100312001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6800749 + ... + 9407251.

Almost surely, 2^{21123100312000} is an apocalyptic number.

21123100312000 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 21123100312000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26181509024736).

21123100312000 is an abundant number, since it is smaller than the sum of its proper divisors (31239917737472).

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

21123100312000 is a wasteful number, since it uses less digits than its factorization.

21123100312000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2607543 (or 2607523 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21123100312000 its reverse (21300132112), we get a palindrome (21144400444112).

The spelling of 21123100312000 in words is "twenty-one trillion, one hundred twenty-three billion, one hundred million, three hundred twelve thousand".