1266761505 has 16 divisors (see below), whose sum is σ = 2027772864. Its totient is φ = 675288000.

The previous prime is 1266761479. The next prime is 1266761539. The reversal of 1266761505 is 5051676621.

It is not a de Polignac number, because 1266761505 - 2⁵ = 1266761473 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15007 + ... + 52523.

It is an arithmetic number, because the mean of its divisors is an integer number (126735804).

Almost surely, 2^1266761505 is an apocalyptic number.

1266761505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1266761505 is a deficient number, since it is larger than the sum of its proper divisors (761011359).

1266761505 is a wasteful number, since it uses less digits than its factorization.

1266761505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39776.

The product of its (nonzero) digits is 75600, while the sum is 39.

The square root of 1266761505 is about 35591.5931787269. The cubic root of 1266761505 is about 1082.0108584139.

The spelling of 1266761505 in words is "one billion, two hundred sixty-six million, seven hundred sixty-one thousand, five hundred five".