1266547997 has 16 divisors (see below), whose sum is σ = 1535976960. Its totient is φ = 1028548800.

The previous prime is 1266547981. The next prime is 1266548027. The reversal of 1266547997 is 7997456621.

It is a cyclic number.

It is not a de Polignac number, because 1266547997 - 2⁴ = 1266547981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266547907) 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, 138422 + ... + 147287.

It is an arithmetic number, because the mean of its divisors is an integer number (95998560).

Almost surely, 2^1266547997 is an apocalyptic number.

It is an amenable number.

1266547997 is a deficient number, since it is larger than the sum of its proper divisors (269428963).

1266547997 is a wasteful number, since it uses less digits than its factorization.

1266547997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 285764.

The product of its digits is 5715360, while the sum is 56.

The square root of 1266547997 is about 35588.5936361638. The cubic root of 1266547997 is about 1081.9500653460.

The spelling of 1266547997 in words is "one billion, two hundred sixty-six million, five hundred forty-seven thousand, nine hundred ninety-seven".