1261081206 has 96 divisors (see below), whose sum is σ = 3416774400. Its totient is φ = 326571840.

The previous prime is 1261081193. The next prime is 1261081229. The reversal of 1261081206 is 6021801621.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1261081206.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 537985 + ... + 540323.

It is an arithmetic number, because the mean of its divisors is an integer number (35591400).

Almost surely, 2^1261081206 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261081206, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1708387200).

1261081206 is an abundant number, since it is smaller than the sum of its proper divisors (2155693194).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261081206 is a wasteful number, since it uses less digits than its factorization.

1261081206 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2754 (or 2751 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 1261081206 is about 35511.7051970192. The cubic root of 1261081206 is about 1080.3911494704.

Adding to 1261081206 its reverse (6021801621), we get a palindrome (7282882827).

The spelling of 1261081206 in words is "one billion, two hundred sixty-one million, eighty-one thousand, two hundred six".