121131100020 has 48 divisors (see below), whose sum is σ = 387619521408. Its totient is φ = 27687108480.

The previous prime is 121131099997. The next prime is 121131100039. The reversal of 121131100020 is 20001131121.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 121131099969 and 121131100005.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144203271 + ... + 144204110.

It is an arithmetic number, because the mean of its divisors is an integer number (8075406696).

Almost surely, 2^121131100020 is an apocalyptic number.

121131100020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121131100020 is an abundant number, since it is smaller than the sum of its proper divisors (266488421388).

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

121131100020 is a wasteful number, since it uses less digits than its factorization.

121131100020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288407400 (or 288407398 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 12.

Adding to 121131100020 its reverse (20001131121), we get a palindrome (141132231141).

The spelling of 121131100020 in words is "one hundred twenty-one billion, one hundred thirty-one million, one hundred thousand, twenty".