1266440637 has 16 divisors (see below), whose sum is σ = 2105252352. Its totient is φ = 657891120.

The previous prime is 1266440627. The next prime is 1266440641. The reversal of 1266440637 is 7360446621.

It is a happy number.

It is not a de Polignac number, because 1266440637 - 2⁴ = 1266440621 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1266440595 and 1266440604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1266440627) 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 15 ways as a sum of consecutive naturals, for example, 2740983 + ... + 2741444.

It is an arithmetic number, because the mean of its divisors is an integer number (131578272).

Almost surely, 2^1266440637 is an apocalyptic number.

It is an amenable number.

1266440637 is a deficient number, since it is larger than the sum of its proper divisors (838811715).

1266440637 is a wasteful number, since it uses less digits than its factorization.

1266440637 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5482448.

The product of its (nonzero) digits is 145152, while the sum is 39.

The square root of 1266440637 is about 35587.0852557497. The cubic root of 1266440637 is about 1081.9194936815.

It can be divided in two parts, 12664 and 40637, that added together give a triangular number (53301 = T₃₂₆).

The spelling of 1266440637 in words is "one billion, two hundred sixty-six million, four hundred forty thousand, six hundred thirty-seven".