1200013121 has 4 divisors (see below), whose sum is σ = 1222654932. Its totient is φ = 1177371312.

The previous prime is 1200013079. The next prime is 1200013163. The reversal of 1200013121 is 1213100021.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1213100021 = 7 ⋅173300003.

It is an interprime number because it is at equal distance from previous prime (1200013079) and next prime (1200013163).

It can be written as a sum of positive squares in 2 ways, for example, as 874030096 + 325983025 = 29564^2 + 18055^2 .

It is a cyclic number.

It is not a de Polignac number, because 1200013121 - 2²⁶ = 1132904257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1200013021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11320826 + ... + 11320931.

It is an arithmetic number, because the mean of its divisors is an integer number (305663733).

Almost surely, 2^1200013121 is an apocalyptic number.

It is an amenable number.

1200013121 is a deficient number, since it is larger than the sum of its proper divisors (22641811).

1200013121 is an equidigital number, since it uses as much as digits as its factorization.

1200013121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22641810.

The product of its (nonzero) digits is 12, while the sum is 11.

The square root of 1200013121 is about 34641.2055361819. The cubic root of 1200013121 is about 1062.6624422638.

Adding to 1200013121 its reverse (1213100021), we get a palindrome (2413113142).

The spelling of 1200013121 in words is "one billion, two hundred million, thirteen thousand, one hundred twenty-one".