1265977755 has 144 divisors (see below), whose sum is σ = 2692497600. Its totient is φ = 559312128.

The previous prime is 1265977711. The next prime is 1265977781. The reversal of 1265977755 is 5577795621.

It is not a de Polignac number, because 1265977755 - 2⁷ = 1265977627 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 8496421 + ... + 8496569.

It is an arithmetic number, because the mean of its divisors is an integer number (18697900).

Almost surely, 2^1265977755 is an apocalyptic number.

1265977755 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1265977755 is an abundant number, since it is smaller than the sum of its proper divisors (1426519845).

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

1265977755 is an frugal number, since it uses more digits than its factorization.

1265977755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222 (or 201 counting only the distinct ones).

The product of its digits is 4630500, while the sum is 54.

The square root of 1265977755 is about 35580.5811503972. The cubic root of 1265977755 is about 1081.7876643453.

The spelling of 1265977755 in words is "one billion, two hundred sixty-five million, nine hundred seventy-seven thousand, seven hundred fifty-five".