126138661 has 16 divisors (see below), whose sum is σ = 146211840. Its totient is φ = 107714880.

The previous prime is 126138643. The next prime is 126138743. The reversal of 126138661 is 166831621.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 126138661 - 2⁹ = 126138149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126138611) 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 15 ways as a sum of consecutive naturals, for example, 6460 + ... + 17146.

It is an arithmetic number, because the mean of its divisors is an integer number (9138240).

Almost surely, 2^126138661 is an apocalyptic number.

126138661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

126138661 is a deficient number, since it is larger than the sum of its proper divisors (20073179).

126138661 is a wasteful number, since it uses less digits than its factorization.

126138661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10764.

The product of its digits is 10368, while the sum is 34.

The square root of 126138661 is about 11231.1469138285. The cubic root of 126138661 is about 501.5136279040.

The spelling of 126138661 in words is "one hundred twenty-six million, one hundred thirty-eight thousand, six hundred sixty-one".