1266456865 has 16 divisors (see below), whose sum is σ = 1528450560. Its totient is φ = 1007383360.

The previous prime is 1266456853. The next prime is 1266456869. The reversal of 1266456865 is 5686546621.

It is not a de Polignac number, because 1266456865 - 2²⁷ = 1132239137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1266456869) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 772827 + ... + 774463.

It is an arithmetic number, because the mean of its divisors is an integer number (95528160).

Almost surely, 2^1266456865 is an apocalyptic number.

It is an amenable number.

1266456865 is a deficient number, since it is larger than the sum of its proper divisors (261993695).

1266456865 is a wasteful number, since it uses less digits than its factorization.

1266456865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2432.

The product of its digits is 2073600, while the sum is 49.

The square root of 1266456865 is about 35587.3132590815. The cubic root of 1266456865 is about 1081.9241148521.

The spelling of 1266456865 in words is "one billion, two hundred sixty-six million, four hundred fifty-six thousand, eight hundred sixty-five".