1266761263 has 4 divisors (see below), whose sum is σ = 1268898048. Its totient is φ = 1264624480.

The previous prime is 1266761219. The next prime is 1266761333. The reversal of 1266761263 is 3621676621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3621676621 = 19 ⋅190614559.

It is a cyclic number.

It is not a de Polignac number, because 1266761263 - 2¹⁷ = 1266630191 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266761203) 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, 1067503 + ... + 1068688.

It is an arithmetic number, because the mean of its divisors is an integer number (317224512).

Almost surely, 2^1266761263 is an apocalyptic number.

1266761263 is a deficient number, since it is larger than the sum of its proper divisors (2136785).

1266761263 is an equidigital number, since it uses as much as digits as its factorization.

1266761263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2136784.

The product of its digits is 108864, while the sum is 40.

The square root of 1266761263 is about 35591.5897790475. The cubic root of 1266761263 is about 1082.0107895121.

The spelling of 1266761263 in words is "one billion, two hundred sixty-six million, seven hundred sixty-one thousand, two hundred sixty-three".