1021100120 has 32 divisors (see below), whose sum is σ = 2340828720. Its totient is φ = 400732800.

The previous prime is 1021100099. The next prime is 1021100141. The reversal of 1021100120 is 210011201.

It is an interprime number because it is at equal distance from previous prime (1021100099) and next prime (1021100141).

It is a Harshad number since it is a multiple of its sum of digits (8).

It is a junction number, because it is equal to n+sod(n) for n = 1021100098 and 1021100107.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 238706 + ... + 242945.

Almost surely, 2^1021100120 is an apocalyptic number.

1021100120 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021100120 is an abundant number, since it is smaller than the sum of its proper divisors (1319728600).

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

1021100120 is a wasteful number, since it uses less digits than its factorization.

1021100120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481715 (or 481711 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1021100120 is about 31954.6572505480. The cubic root of 1021100120 is about 1006.9844768422.

Adding to 1021100120 its reverse (210011201), we get a palindrome (1231111321).

The spelling of 1021100120 in words is "one billion, twenty-one million, one hundred thousand, one hundred twenty".