1211401131 has 4 divisors (see below), whose sum is σ = 1615201512. Its totient is φ = 807600752.

The previous prime is 1211401123. The next prime is 1211401153. The reversal of 1211401131 is 1311041121.

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 1211401131 - 2³ = 1211401123 is a prime.

It is a super-3 number, since 3×1211401131³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 1211401131.

It is not an unprimeable number, because it can be changed into a prime (1211401531) 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 3 ways as a sum of consecutive naturals, for example, 201900186 + ... + 201900191.

It is an arithmetic number, because the mean of its divisors is an integer number (403800378).

Almost surely, 2^1211401131 is an apocalyptic number.

1211401131 is a deficient number, since it is larger than the sum of its proper divisors (403800381).

1211401131 is an equidigital number, since it uses as much as digits as its factorization.

1211401131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 403800380.

The product of its (nonzero) digits is 24, while the sum is 15.

The square root of 1211401131 is about 34805.1882770371. The cubic root of 1211401131 is about 1066.0133861885.

Adding to 1211401131 its reverse (1311041121), we get a palindrome (2522442252).

The spelling of 1211401131 in words is "one billion, two hundred eleven million, four hundred one thousand, one hundred thirty-one".