1266887787 has 24 divisors (see below), whose sum is σ = 1965933648. Its totient is φ = 722641920.

The previous prime is 1266887761. The next prime is 1266887813. The reversal of 1266887787 is 7877886621.

It is an interprime number because it is at equal distance from previous prime (1266887761) and next prime (1266887813).

It is not a de Polignac number, because 1266887787 - 2⁶ = 1266887723 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1266887787.

It is not an unprimeable number, because it can be changed into a prime (1266887717) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 96478 + ... + 108819.

It is an arithmetic number, because the mean of its divisors is an integer number (81913902).

Almost surely, 2^1266887787 is an apocalyptic number.

1266887787 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

1266887787 is a deficient number, since it is larger than the sum of its proper divisors (699045861).

1266887787 is a wasteful number, since it uses less digits than its factorization.

1266887787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205339 (or 205328 counting only the distinct ones).

The product of its digits is 12644352, while the sum is 60.

The square root of 1266887787 is about 35593.3671770458. The cubic root of 1266887787 is about 1082.0468120259.

The spelling of 1266887787 in words is "one billion, two hundred sixty-six million, eight hundred eighty-seven thousand, seven hundred eighty-seven".