1266221646 has 40 divisors (see below), whose sum is σ = 2876168064. Its totient is φ = 416288160.

The previous prime is 1266221639. The next prime is 1266221647. The reversal of 1266221646 is 6461226621.

1266221646 is a `hidden beast` number, since 1 + 2 + 6 + 6 + 2 + 2 + 1 + 646 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 1266221646.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266221647) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 41710 + ... + 65361.

Almost surely, 2^1266221646 is an apocalyptic number.

1266221646 is an abundant number, since it is smaller than the sum of its proper divisors (1609946418).

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

1266221646 is a wasteful number, since it uses less digits than its factorization.

1266221646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107158 (or 107149 counting only the distinct ones).

The product of its digits is 41472, while the sum is 36.

The square root of 1266221646 is about 35584.0082902418. The cubic root of 1266221646 is about 1081.8571287924.

The spelling of 1266221646 in words is "one billion, two hundred sixty-six million, two hundred twenty-one thousand, six hundred forty-six".