21121220101000 has 64 divisors (see below), whose sum is σ = 49582574271360. Its totient is φ = 8421322360000.

The previous prime is 21121220100961. The next prime is 21121220101039. The reversal of 21121220101000 is 10102212112.

It is an interprime number because it is at equal distance from previous prime (21121220100961) and next prime (21121220101039).

It is a super-2 number, since 2×21121220101000² (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 15 ways as a sum of consecutive naturals, for example, 33645946 + ... + 34267945.

It is an arithmetic number, because the mean of its divisors is an integer number (774727722990).

Almost surely, 2^{21121220101000} is an apocalyptic number.

21121220101000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21121220101000 is an abundant number, since it is smaller than the sum of its proper divisors (28461354170360).

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

21121220101000 is a wasteful number, since it uses less digits than its factorization.

21121220101000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67914223 (or 67914209 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21121220101000 its reverse (10102212112), we get a palindrome (21131322313112).

The spelling of 21121220101000 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred twenty million, one hundred one thousand".