1201312111 has 4 divisors (see below), whose sum is σ = 1201384800. Its totient is φ = 1201239424.

The previous prime is 1201312109. The next prime is 1201312127. The reversal of 1201312111 is 1112131021.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1201312111 - 2¹ = 1201312109 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1201312091 and 1201312100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201312141) 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 3 ways as a sum of consecutive naturals, for example, 1770 + ... + 49048.

It is an arithmetic number, because the mean of its divisors is an integer number (300346200).

Almost surely, 2^1201312111 is an apocalyptic number.

1201312111 is a deficient number, since it is larger than the sum of its proper divisors (72689).

1201312111 is an equidigital number, since it uses as much as digits as its factorization.

1201312111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72688.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 1201312111 is about 34659.9496681689. The cubic root of 1201312111 is about 1063.0457408796.

Adding to 1201312111 its reverse (1112131021), we get a palindrome (2313443132).

The spelling of 1201312111 in words is "one billion, two hundred one million, three hundred twelve thousand, one hundred eleven".