126721135 has 16 divisors (see below), whose sum is σ = 154535040. Its totient is φ = 99740160.

The previous prime is 126721123. The next prime is 126721139. The reversal of 126721135 is 531127621.

It is a happy number.

It is not a de Polignac number, because 126721135 - 2¹⁷ = 126590063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126721139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 213399 + ... + 213991.

It is an arithmetic number, because the mean of its divisors is an integer number (9658440).

Almost surely, 2^126721135 is an apocalyptic number.

126721135 is a deficient number, since it is larger than the sum of its proper divisors (27813905).

126721135 is an equidigital number, since it uses as much as digits as its factorization.

126721135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1218.

The product of its digits is 2520, while the sum is 28.

The square root of 126721135 is about 11257.0482365494. The cubic root of 126721135 is about 502.2843938614.

Adding to 126721135 its reverse (531127621), we get a palindrome (657848756).

The spelling of 126721135 in words is "one hundred twenty-six million, seven hundred twenty-one thousand, one hundred thirty-five".