1266136513 has 4 divisors (see below), whose sum is σ = 1267302400. Its totient is φ = 1264970628.

The previous prime is 1266136507. The next prime is 1266136537. The reversal of 1266136513 is 3156316621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1266136513 - 2²⁹ = 729265601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1266136583) 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, 581313 + ... + 583486.

It is an arithmetic number, because the mean of its divisors is an integer number (316825600).

Almost surely, 2^1266136513 is an apocalyptic number.

It is an amenable number.

1266136513 is a deficient number, since it is larger than the sum of its proper divisors (1165887).

1266136513 is a wasteful number, since it uses less digits than its factorization.

1266136513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1165886.

The product of its digits is 19440, while the sum is 34.

The square root of 1266136513 is about 35582.8120445813. The cubic root of 1266136513 is about 1081.8328824299.

The spelling of 1266136513 in words is "one billion, two hundred sixty-six million, one hundred thirty-six thousand, five hundred thirteen".