1266805000 has 40 divisors (see below), whose sum is σ = 2968135830. Its totient is φ = 506720000.

The previous prime is 1266804991. The next prime is 1266805009. The reversal of 1266805000 is 5086621.

It is an interprime number because it is at equal distance from previous prime (1266804991) and next prime (1266805009).

It can be written as a sum of positive squares in 5 ways, for example, as 2149156 + 1264655844 = 1466^2 + 35562^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 1266805000.

It is not an unprimeable number, because it can be changed into a prime (1266805009) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 121681 + ... + 131680.

Almost surely, 2^1266805000 is an apocalyptic number.

1266805000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1266805000 is an abundant number, since it is smaller than the sum of its proper divisors (1701330830).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1266805000 is an equidigital number, since it uses as much as digits as its factorization.

1266805000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253387 (or 253368 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 1266805000 is about 35592.2042026059. The cubic root of 1266805000 is about 1082.0232420982.

The spelling of 1266805000 in words is "one billion, two hundred sixty-six million, eight hundred five thousand".