100221001020 has 144 divisors (see below), whose sum is σ = 351619107840. Its totient is φ = 22631637888.

The previous prime is 100221001009. The next prime is 100221001031. The reversal of 100221001020 is 20100122001.

It is an interprime number because it is at equal distance from previous prime (100221001009) and next prime (100221001031).

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

It is a junction number, because it is equal to n+sod(n) for n = 100221000993 and 100221001011.

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, 374580 + ... + 583739.

It is an arithmetic number, because the mean of its divisors is an integer number (2441799360).

Almost surely, 2^100221001020 is an apocalyptic number.

100221001020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

100221001020 is an abundant number, since it is smaller than the sum of its proper divisors (251398106820).

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

100221001020 is a wasteful number, since it uses less digits than its factorization.

100221001020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 958424 (or 958419 counting only the distinct ones).

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

Adding to 100221001020 its reverse (20100122001), we get a palindrome (120321123021).

The spelling of 100221001020 in words is "one hundred billion, two hundred twenty-one million, one thousand, twenty".