1200121100 has 18 divisors (see below), whose sum is σ = 2604263004. Its totient is φ = 480048400.

The previous prime is 1200121093. The next prime is 1200121121. The reversal of 1200121100 is 11210021.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6000506 + ... + 6000705.

It is an arithmetic number, because the mean of its divisors is an integer number (144681278).

Almost surely, 2^1200121100 is an apocalyptic number.

1200121100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1200121100 is an abundant number, since it is smaller than the sum of its proper divisors (1404141904).

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

1200121100 is a wasteful number, since it uses less digits than its factorization.

1200121100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12001225 (or 12001218 counting only the distinct ones).

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

The square root of 1200121100 is about 34642.7640352210. The cubic root of 1200121100 is about 1062.6943146337.

Adding to 1200121100 its reverse (11210021), we get a palindrome (1211331121).

The spelling of 1200121100 in words is "one billion, two hundred million, one hundred twenty-one thousand, one hundred".