21100110121000 has 64 divisors (see below), whose sum is σ = 49929024834000. Its totient is φ = 8345212057600.

The previous prime is 21100110120983. The next prime is 21100110121003. The reversal of 21100110121000 is 12101100112.

It can be written as a sum of positive squares in 8 ways, for example, as 1957262556484 + 19142847564516 = 1399022^2 + 4375254^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (21100110121003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118450945 + ... + 118628944.

Almost surely, 2^{21100110121000} is an apocalyptic number.

21100110121000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21100110121000 is an abundant number, since it is smaller than the sum of its proper divisors (28828914713000).

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

21100110121000 is a wasteful number, since it uses less digits than its factorization.

21100110121000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237079999 (or 237079985 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21100110121000 its reverse (12101100112), we get a palindrome (21112211221112).

The spelling of 21100110121000 in words is "twenty-one trillion, one hundred billion, one hundred ten million, one hundred twenty-one thousand".