1201100121 has 48 divisors (see below), whose sum is σ = 1904448000. Its totient is φ = 725003136.

The previous prime is 1201100107. The next prime is 1201100137. The reversal of 1201100121 is 1210011021.

It is a happy number.

It is not a de Polignac number, because 1201100121 - 2⁶ = 1201100057 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (1201100101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1839031 + ... + 1839683.

It is an arithmetic number, because the mean of its divisors is an integer number (39676000).

Almost surely, 2^1201100121 is an apocalyptic number.

It is an amenable number.

1201100121 is a deficient number, since it is larger than the sum of its proper divisors (703347879).

1201100121 is a wasteful number, since it uses less digits than its factorization.

1201100121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 950 (or 947 counting only the distinct ones).

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

The square root of 1201100121 is about 34656.8913926220. The cubic root of 1201100121 is about 1062.9832069436.

Adding to 1201100121 its reverse (1210011021), we get a palindrome (2411111142).

The spelling of 1201100121 in words is "one billion, two hundred one million, one hundred thousand, one hundred twenty-one".