1266628881 has 48 divisors (see below), whose sum is σ = 2030495040. Its totient is φ = 699753600.

The previous prime is 1266628879. The next prime is 1266628919. The reversal of 1266628881 is 1888266621.

It is a happy number.

It is not a de Polignac number, because 1266628881 - 2¹ = 1266628879 is a prime.

It is a super-2 number, since 2×1266628881² = 3208697444366624322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1266628881.

It is not an unprimeable number, because it can be changed into a prime (1266628861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 972931 + ... + 974231.

It is an arithmetic number, because the mean of its divisors is an integer number (42301980).

Almost surely, 2^1266628881 is an apocalyptic number.

It is an amenable number.

1266628881 is a deficient number, since it is larger than the sum of its proper divisors (763866159).

1266628881 is a wasteful number, since it uses less digits than its factorization.

1266628881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1534 (or 1527 counting only the distinct ones).

The product of its digits is 442368, while the sum is 48.

The square root of 1266628881 is about 35589.7299933562. The cubic root of 1266628881 is about 1081.9730966053.

The spelling of 1266628881 in words is "one billion, two hundred sixty-six million, six hundred twenty-eight thousand, eight hundred eighty-one".