126285778081 has 4 divisors (see below), whose sum is σ = 132932398000. Its totient is φ = 119639158164.

The previous prime is 126285778079. The next prime is 126285778093. The reversal of 126285778081 is 180877582621.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 180877582621 = 89 ⋅2032332389.

It is a cyclic number.

It is not a de Polignac number, because 126285778081 - 2¹ = 126285778079 is a prime.

It is a super-2 number, since 2×126285778081² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (126285778001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3323309931 + ... + 3323309968.

It is an arithmetic number, because the mean of its divisors is an integer number (33233099500).

Almost surely, 2^126285778081 is an apocalyptic number.

It is an amenable number.

126285778081 is a deficient number, since it is larger than the sum of its proper divisors (6646619919).

126285778081 is an equidigital number, since it uses as much as digits as its factorization.

126285778081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6646619918.

The product of its (nonzero) digits is 3010560, while the sum is 55.

The spelling of 126285778081 in words is "one hundred twenty-six billion, two hundred eighty-five million, seven hundred seventy-eight thousand, eighty-one".