126661777601 has 4 divisors (see below), whose sum is σ = 126670395312. Its totient is φ = 126653159892.

The previous prime is 126661777591. The next prime is 126661777621. The reversal of 126661777601 is 106777166621.

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.

It is a cyclic number.

It is not a de Polignac number, because 126661777601 - 2³⁰ = 125588035777 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 126661777601.

It is not an unprimeable number, because it can be changed into a prime (126661777621) 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 3 ways as a sum of consecutive naturals, for example, 4286771 + ... + 4316216.

It is an arithmetic number, because the mean of its divisors is an integer number (31667598828).

Almost surely, 2^126661777601 is an apocalyptic number.

It is an amenable number.

126661777601 is a deficient number, since it is larger than the sum of its proper divisors (8617711).

126661777601 is an equidigital number, since it uses as much as digits as its factorization.

126661777601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8617710.

The product of its (nonzero) digits is 889056, while the sum is 50.

The spelling of 126661777601 in words is "one hundred twenty-six billion, six hundred sixty-one million, seven hundred seventy-seven thousand, six hundred one".