126832721 has 4 divisors (see below), whose sum is σ = 129926244. Its totient is φ = 123739200.

The previous prime is 126832703. The next prime is 126832723. The reversal of 126832721 is 127238621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 127238621 = 41 ⋅3103381.

It can be written as a sum of positive squares in 2 ways, for example, as 69072721 + 57760000 = 8311^2 + 7600^2 .

It is a cyclic number.

It is not a de Polignac number, because 126832721 - 2¹⁰ = 126831697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (126832723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1546700 + ... + 1546781.

It is an arithmetic number, because the mean of its divisors is an integer number (32481561).

Almost surely, 2^126832721 is an apocalyptic number.

It is an amenable number.

126832721 is a deficient number, since it is larger than the sum of its proper divisors (3093523).

126832721 is an equidigital number, since it uses as much as digits as its factorization.

126832721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3093522.

The product of its digits is 8064, while the sum is 32.

The square root of 126832721 is about 11262.0034185752. The cubic root of 126832721 is about 502.4317817015.

The spelling of 126832721 in words is "one hundred twenty-six million, eight hundred thirty-two thousand, seven hundred twenty-one".