1266942587 has 4 divisors (see below), whose sum is σ = 1268730240. Its totient is φ = 1265154936.

The previous prime is 1266942563. The next prime is 1266942613. The reversal of 1266942587 is 7852496621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7852496621 = 769 ⋅10211309.

It is a cyclic number.

It is not a de Polignac number, because 1266942587 - 2¹⁰ = 1266941563 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1266942487) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 892763 + ... + 894180.

It is an arithmetic number, because the mean of its divisors is an integer number (317182560).

Almost surely, 2^1266942587 is an apocalyptic number.

1266942587 is a deficient number, since it is larger than the sum of its proper divisors (1787653).

1266942587 is an equidigital number, since it uses as much as digits as its factorization.

1266942587 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1787652.

The product of its digits is 1451520, while the sum is 50.

The square root of 1266942587 is about 35594.1369750694. The cubic root of 1266942587 is about 1082.0624133315.

The spelling of 1266942587 in words is "one billion, two hundred sixty-six million, nine hundred forty-two thousand, five hundred eighty-seven".