1200020121 has 24 divisors (see below), whose sum is σ = 1799301504. Its totient is φ = 770139360.

The previous prime is 1200020093. The next prime is 1200020141. The reversal of 1200020121 is 1210200021.

It is not a de Polignac number, because 1200020121 - 2¹⁰ = 1200019097 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 (1200020141) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2550 + ... + 49056.

It is an arithmetic number, because the mean of its divisors is an integer number (74970896).

Almost surely, 2^1200020121 is an apocalyptic number.

It is an amenable number.

1200020121 is a deficient number, since it is larger than the sum of its proper divisors (599281383).

1200020121 is a wasteful number, since it uses less digits than its factorization.

1200020121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46621 (or 46618 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1200020121 is about 34641.3065717793. The cubic root of 1200020121 is about 1062.6645085253.

Adding to 1200020121 its reverse (1210200021), we get a palindrome (2410220142).

The spelling of 1200020121 in words is "one billion, two hundred million, twenty thousand, one hundred twenty-one".