1311020121 has 16 divisors (see below), whose sum is σ = 1844091200. Its totient is φ = 826184448.

The previous prime is 1311020099. The next prime is 1311020147. The reversal of 1311020121 is 1210201131.

It is not a de Polignac number, because 1311020121 - 2⁹ = 1311019609 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1311020097 and 1311020106.

It is not an unprimeable number, because it can be changed into a prime (1311000121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 885 + ... + 51213.

It is an arithmetic number, because the mean of its divisors is an integer number (115255700).

Almost surely, 2^1311020121 is an apocalyptic number.

It is an amenable number.

1311020121 is a deficient number, since it is larger than the sum of its proper divisors (533071079).

1311020121 is a wasteful number, since it uses less digits than its factorization.

1311020121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50808.

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

The square root of 1311020121 is about 36208.0118343993. The cubic root of 1311020121 is about 1094.4681280942.

Adding to 1311020121 its reverse (1210201131), we get a palindrome (2521221252).

The spelling of 1311020121 in words is "one billion, three hundred eleven million, twenty thousand, one hundred twenty-one".