1261435113 has 12 divisors (see below), whose sum is σ = 1889557488. Its totient is φ = 840956580.

The previous prime is 1261435111. The next prime is 1261435171. The reversal of 1261435113 is 3115341621.

It is a happy number.

1261435113 is a `hidden beast` number, since 1 + 2 + 6 + 143 + 511 + 3 = 666.

It is not a de Polignac number, because 1261435113 - 2¹ = 1261435111 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1261435111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2595303 + ... + 2595788.

It is an arithmetic number, because the mean of its divisors is an integer number (157463124).

Almost surely, 2^1261435113 is an apocalyptic number.

It is an amenable number.

1261435113 is a deficient number, since it is larger than the sum of its proper divisors (628122375).

1261435113 is an frugal number, since it uses more digits than its factorization.

1261435113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5191106 (or 5191094 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 1261435113 is about 35516.6878100985. The cubic root of 1261435113 is about 1080.4922062002.

Adding to 1261435113 its reverse (3115341621), we get a palindrome (4376776734).

The spelling of 1261435113 in words is "one billion, two hundred sixty-one million, four hundred thirty-five thousand, one hundred thirteen".