100100021220 has 72 divisors (see below), whose sum is σ = 304613225280. Its totient is φ = 26607493440.

The previous prime is 100100021179. The next prime is 100100021257. The reversal of 100100021220 is 22120001001.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 838090 + ... + 950049.

It is an arithmetic number, because the mean of its divisors is an integer number (4230739240).

Almost surely, 2^100100021220 is an apocalyptic number.

100100021220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

100100021220 is an abundant number, since it is smaller than the sum of its proper divisors (204513204060).

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

100100021220 is a wasteful number, since it uses less digits than its factorization.

100100021220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1788465 (or 1788460 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 100100021220 its reverse (22120001001), we get a palindrome (122220022221).

The spelling of 100100021220 in words is "one hundred billion, one hundred million, twenty-one thousand, two hundred twenty".