126729592081 has 9 divisors (see below), whose sum is σ = 127243938171. Its totient is φ = 126217321032.

The previous prime is 126729592061. The next prime is 126729592091. The reversal of 126729592081 is 180295927621.

The square root of 126729592081 is 355991.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 7093850625 + 119635741456 = 84225^2 + 345884^2 .

It is not a de Polignac number, because 126729592081 - 2⁷ = 126729591953 is a prime.

It is a super-4 number, since 4×126729592081⁴ (a number of 46 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126729592061) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 112848586 + ... + 112849708.

Almost surely, 2^126729592081 is an apocalyptic number.

126729592081 is the 355991-st square number.

126729592081 is the 177996-th centered octagonal number.

It is an amenable number.

126729592081 is a deficient number, since it is larger than the sum of its proper divisors (514346090).

126729592081 is an frugal number, since it uses more digits than its factorization.

126729592081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2880 (or 1440 counting only the distinct ones).

The product of its (nonzero) digits is 1088640, while the sum is 52.

The spelling of 126729592081 in words is "one hundred twenty-six billion, seven hundred twenty-nine million, five hundred ninety-two thousand, eighty-one".