121004028 has 72 divisors (see below), whose sum is σ = 326119248. Its totient is φ = 37698048.

The previous prime is 121003999. The next prime is 121004041. The reversal of 121004028 is 820400121.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 121004028.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99150 + ... + 100362.

It is an arithmetic number, because the mean of its divisors is an integer number (4529434).

Almost surely, 2^121004028 is an apocalyptic number.

121004028 is a gapful number since it is divisible by the number (18) 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 121004028, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163059624).

121004028 is an abundant number, since it is smaller than the sum of its proper divisors (205115220).

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

121004028 is a wasteful number, since it uses less digits than its factorization.

121004028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1403 (or 1398 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 121004028 is about 11000.1830893854. The cubic root of 121004028 is about 494.6142326497.

Adding to 121004028 its reverse (820400121), we get a palindrome (941404149).

The spelling of 121004028 in words is "one hundred twenty-one million, four thousand, twenty-eight".