126635166391 has 4 divisors (see below), whose sum is σ = 126635882112. Its totient is φ = 126634450672.

The previous prime is 126635166349. The next prime is 126635166419. The reversal of 126635166391 is 193661536621.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 126635166391 - 2⁷ = 126635166263 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126635161391) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 122235 + ... + 517891.

It is an arithmetic number, because the mean of its divisors is an integer number (31658970528).

Almost surely, 2^126635166391 is an apocalyptic number.

126635166391 is a deficient number, since it is larger than the sum of its proper divisors (715721).

126635166391 is an equidigital number, since it uses as much as digits as its factorization.

126635166391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 715720.

The product of its digits is 1049760, while the sum is 49.

The spelling of 126635166391 in words is "one hundred twenty-six billion, six hundred thirty-five million, one hundred sixty-six thousand, three hundred ninety-one".