20101210100100 has 108 divisors (see below), whose sum is σ = 63175044608676. Its totient is φ = 5345951765760.

The previous prime is 20101210100053. The next prime is 20101210100119. The reversal of 20101210100100 is 100101210102.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1399806061956 + 18701404038144 = 1183134^2 + 4324512^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 29603547 + ... + 30274946.

It is an arithmetic number, because the mean of its divisors is an integer number (584954116747).

Almost surely, 2^{20101210100100} is an apocalyptic number.

20101210100100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20101210100100 is an abundant number, since it is smaller than the sum of its proper divisors (43073834508576).

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

20101210100100 is a wasteful number, since it uses less digits than its factorization.

20101210100100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59878886 (or 59878876 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 20101210100100 its reverse (100101210102), we get a palindrome (20201311310202).

The spelling of 20101210100100 in words is "twenty trillion, one hundred one billion, two hundred ten million, one hundred thousand, one hundred".