21120001000000 has 784 divisors, whose sum is σ = 66736058267520. Its totient is φ = 6455808000000.

The previous prime is 21120000999967. The next prime is 21120001000003. The reversal of 21120001000000 is 10002112.

It is a Harshad number since it is a multiple of its sum of digits (7).

It is not an unprimeable number, because it can be changed into a prime (21120001000003) by changing a digit.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 2260995330 + ... + 2261004670.

Almost surely, 2^{21120001000000} is an apocalyptic number.

21120001000000 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 21120001000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33368029133760).

21120001000000 is an abundant number, since it is smaller than the sum of its proper divisors (45616057267520).

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

21120001000000 is an frugal number, since it uses more digits than its factorization.

21120001000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9426 (or 9391 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 21120001000000 its reverse (10002112), we get a palindrome (21120011002112).

The spelling of 21120001000000 in words is "twenty-one trillion, one hundred twenty billion, one million", and thus it is an aban number.