126559921165 has 16 divisors (see below), whose sum is σ = 161979324912. Its totient is φ = 94596603904.

The previous prime is 126559921129. The next prime is 126559921181. The reversal of 126559921165 is 561129955621.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 21575496996 + 104984424169 = 146886^2 + 324013^2 .

It is not a de Polignac number, because 126559921165 - 2¹⁵ = 126559888397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5422444 + ... + 5445733.

It is an arithmetic number, because the mean of its divisors is an integer number (10123707807).

Almost surely, 2^126559921165 is an apocalyptic number.

It is an amenable number.

126559921165 is a deficient number, since it is larger than the sum of its proper divisors (35419403747).

126559921165 is a wasteful number, since it uses less digits than its factorization.

126559921165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10868336.

The product of its digits is 1458000, while the sum is 52.

The spelling of 126559921165 in words is "one hundred twenty-six billion, five hundred fifty-nine million, nine hundred twenty-one thousand, one hundred sixty-five".