1266551 has 16 divisors (see below), whose sum is σ = 1578528. Its totient is φ = 998400.

The previous prime is 1266539. The next prime is 1266557. The reversal of 1266551 is 1556621.

It is not a de Polignac number, because 1266551 - 2⁶ = 1266487 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1266551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266557) 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 15 ways as a sum of consecutive naturals, for example, 2171 + ... + 2691.

It is an arithmetic number, because the mean of its divisors is an integer number (98658).

2^1266551 is an apocalyptic number.

1266551 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1266551 is a deficient number, since it is larger than the sum of its proper divisors (311977).

1266551 is a wasteful number, since it uses less digits than its factorization.

1266551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 562.

The product of its digits is 1800, while the sum is 26.

The square root of 1266551 is about 1125.4114803040. The cubic root of 1266551 is about 108.1950920451.

The spelling of 1266551 in words is "one million, two hundred sixty-six thousand, five hundred fifty-one".