20100021210100 has 144 divisors (see below), whose sum is σ = 47315542080240. Its totient is φ = 7367429836800.

The previous prime is 20100021210029. The next prime is 20100021210151. The reversal of 20100021210100 is 101212000102.

It can be written as a sum of positive squares in 24 ways, for example, as 10733997533284 + 9366023676816 = 3276278^2 + 3060396^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 148591296 + ... + 148726504.

It is an arithmetic number, because the mean of its divisors is an integer number (328580153335).

Almost surely, 2^{20100021210100} is an apocalyptic number.

20100021210100 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 20100021210100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23657771040120).

20100021210100 is an abundant number, since it is smaller than the sum of its proper divisors (27215520870140).

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

20100021210100 is a wasteful number, since it uses less digits than its factorization.

20100021210100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136070 (or 136063 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 10.

Adding to 20100021210100 its reverse (101212000102), we get a palindrome (20201233210202).

The spelling of 20100021210100 in words is "twenty trillion, one hundred billion, twenty-one million, two hundred ten thousand, one hundred".