1266531553 has 8 divisors (see below), whose sum is σ = 1450567872. Its totient is φ = 1083271056.

The previous prime is 1266531551. The next prime is 1266531557. The reversal of 1266531553 is 3551356621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1266531553 - 2¹ = 1266531551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1266531551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 190450 + ... + 196987.

It is an arithmetic number, because the mean of its divisors is an integer number (181320984).

Almost surely, 2^1266531553 is an apocalyptic number.

It is an amenable number.

1266531553 is a deficient number, since it is larger than the sum of its proper divisors (184036319).

1266531553 is an equidigital number, since it uses as much as digits as its factorization.

1266531553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387911.

The product of its digits is 81000, while the sum is 37.

The square root of 1266531553 is about 35588.3626063352. The cubic root of 1266531553 is about 1081.9453828905.

The spelling of 1266531553 in words is "one billion, two hundred sixty-six million, five hundred thirty-one thousand, five hundred fifty-three".