1266428217 has 16 divisors (see below), whose sum is σ = 1745670080. Its totient is φ = 816141312.

The previous prime is 1266428197. The next prime is 1266428227. The reversal of 1266428217 is 7128246621.

1266428217 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1266428217 - 2⁶ = 1266428153 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1266428227) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38092 + ... + 63117.

It is an arithmetic number, because the mean of its divisors is an integer number (109104380).

Almost surely, 2^1266428217 is an apocalyptic number.

It is an amenable number.

1266428217 is a deficient number, since it is larger than the sum of its proper divisors (479241863).

1266428217 is a wasteful number, since it uses less digits than its factorization.

1266428217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101352.

The product of its digits is 64512, while the sum is 39.

The square root of 1266428217 is about 35586.9107538151. The cubic root of 1266428217 is about 1081.9159568704.

The spelling of 1266428217 in words is "one billion, two hundred sixty-six million, four hundred twenty-eight thousand, two hundred seventeen".