121111001020 has 24 divisors (see below), whose sum is σ = 255650898384. Its totient is φ = 48193391616.

The previous prime is 121111001017. The next prime is 121111001041. The reversal of 121111001020 is 20100111121.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 121111000988 and 121111001006.

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, 15684094 + ... + 15691813.

It is an arithmetic number, because the mean of its divisors is an integer number (10652120766).

Almost surely, 2^121111001020 is an apocalyptic number.

121111001020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121111001020 is an abundant number, since it is smaller than the sum of its proper divisors (134539897364).

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

121111001020 is a wasteful number, since it uses less digits than its factorization.

121111001020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31376109 (or 31376107 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 121111001020 its reverse (20100111121), we get a palindrome (141211112141).

The spelling of 121111001020 in words is "one hundred twenty-one billion, one hundred eleven million, one thousand, twenty".