21001121011120 has 80 divisors (see below), whose sum is σ = 51742430460000. Its totient is φ = 7904907915264.

The previous prime is 21001121011103. The next prime is 21001121011153. The reversal of 21001121011120 is 2111012110012.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-3 number, since 3×21001121011120³ (a number of 41 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21001121011120.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 46137705 + ... + 46590664.

It is an arithmetic number, because the mean of its divisors is an integer number (646780380750).

Almost surely, 2^{21001121011120} is an apocalyptic number.

21001121011120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001121011120 is an abundant number, since it is smaller than the sum of its proper divisors (30741309448880).

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

21001121011120 is a wasteful number, since it uses less digits than its factorization.

21001121011120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92728550 (or 92728544 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 21001121011120 its reverse (2111012110012), we get a palindrome (23112133121132).

The spelling of 21001121011120 in words is "twenty-one trillion, one billion, one hundred twenty-one million, eleven thousand, one hundred twenty".