1211013123 has 4 divisors (see below), whose sum is σ = 1614684168. Its totient is φ = 807342080.

The previous prime is 1211013113. The next prime is 1211013131. The reversal of 1211013123 is 3213101121.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1211013123 - 2⁵ = 1211013091 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1211013103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 201835518 + ... + 201835523.

It is an arithmetic number, because the mean of its divisors is an integer number (403671042).

Almost surely, 2^1211013123 is an apocalyptic number.

1211013123 is a deficient number, since it is larger than the sum of its proper divisors (403671045).

1211013123 is an equidigital number, since it uses as much as digits as its factorization.

1211013123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403671044.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1211013123 is about 34799.6138340643. The cubic root of 1211013123 is about 1065.8995604486.

Adding to 1211013123 its reverse (3213101121), we get a palindrome (4424114244).

The spelling of 1211013123 in words is "one billion, two hundred eleven million, thirteen thousand, one hundred twenty-three".