1213531141 has 4 divisors (see below), whose sum is σ = 1213641900. Its totient is φ = 1213420384.

The previous prime is 1213531139. The next prime is 1213531147. The reversal of 1213531141 is 1411353121.

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 can be written as a sum of positive squares in 2 ways, for example, as 310288225 + 903242916 = 17615^2 + 30054^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213531141 - 2¹ = 1213531139 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1213531147) 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, 36886 + ... + 61543.

It is an arithmetic number, because the mean of its divisors is an integer number (303410475).

Almost surely, 2^1213531141 is an apocalyptic number.

It is an amenable number.

1213531141 is a deficient number, since it is larger than the sum of its proper divisors (110759).

1213531141 is an equidigital number, since it uses as much as digits as its factorization.

1213531141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110758.

The product of its digits is 360, while the sum is 22.

The square root of 1213531141 is about 34835.7738682522. The cubic root of 1213531141 is about 1066.6378117954.

Adding to 1213531141 its reverse (1411353121), we get a palindrome (2624884262).

The spelling of 1213531141 in words is "one billion, two hundred thirteen million, five hundred thirty-one thousand, one hundred forty-one".