121100121000 has 192 divisors, whose sum is σ = 409551152400. Its totient is φ = 32275008000.

The previous prime is 121100120987. The next prime is 121100121011. The reversal of 121100121000 is 121001121.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 20551516164 + 100548604836 = 143358^2 + 317094^2 .

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 47 ways as a sum of consecutive naturals, for example, 24666546 + ... + 24671454.

Almost surely, 2^121100121000 is an apocalyptic number.

121100121000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121100121000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (204775576200).

121100121000 is an abundant number, since it is smaller than the sum of its proper divisors (288451031400).

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

121100121000 is a wasteful number, since it uses less digits than its factorization.

121100121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7677 (or 7660 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 121100121000 its reverse (121001121), we get a palindrome (121221122121).

The spelling of 121100121000 in words is "one hundred twenty-one billion, one hundred million, one hundred twenty-one thousand".