126887809 has 4 divisors (see below), whose sum is σ = 127288404. Its totient is φ = 126487216.

The previous prime is 126887807. The next prime is 126887879. The reversal of 126887809 is 908788621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 908788621 = 13 ⋅69906817.

It can be written as a sum of positive squares in 2 ways, for example, as 69355584 + 57532225 = 8328^2 + 7585^2 .

It is a cyclic number.

It is not a de Polignac number, because 126887809 - 2¹ = 126887807 is a prime.

It is a super-2 number, since 2×126887809² = 32201032145640962, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126887801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199822 + ... + 200455.

It is an arithmetic number, because the mean of its divisors is an integer number (31822101).

Almost surely, 2^126887809 is an apocalyptic number.

It is an amenable number.

126887809 is a deficient number, since it is larger than the sum of its proper divisors (400595).

126887809 is an equidigital number, since it uses as much as digits as its factorization.

126887809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400594.

The product of its (nonzero) digits is 387072, while the sum is 49.

The square root of 126887809 is about 11264.4488990807. The cubic root of 126887809 is about 502.5045125540.

The spelling of 126887809 in words is "one hundred twenty-six million, eight hundred eighty-seven thousand, eight hundred nine".