126617165721856 has 18 divisors (see below), whose sum is σ = 252739733140622. Its totient is φ = 63308582860800.

The previous prime is 126617165721829. The next prime is 126617165721859. The reversal of 126617165721856 is 658127561716621.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 86522739097600 + 40094426624256 = 9301760^2 + 6332016^2 .

It is a Harshad number since it is a multiple of its sum of digits (64).

It is not an unprimeable number, because it can be changed into a prime (126617165721859) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247299151545 + ... + 247299152056.

Almost surely, 2^{126617165721856} is an apocalyptic number.

126617165721856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

126617165721856 is a deficient number, since it is larger than the sum of its proper divisors (126122567418766).

126617165721856 is an frugal number, since it uses more digits than its factorization.

126617165721856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 494598303617 (or 494598303603 counting only the distinct ones).

The product of its digits is 50803200, while the sum is 64.

The spelling of 126617165721856 in words is "one hundred twenty-six trillion, six hundred seventeen billion, one hundred sixty-five million, seven hundred twenty-one thousand, eight hundred fifty-six".