126638593 has 4 divisors (see below), whose sum is σ = 134087940. Its totient is φ = 119189248.

The previous prime is 126638579. The next prime is 126638597. The reversal of 126638593 is 395836621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 395836621 = 3169 ⋅124909.

It can be written as a sum of positive squares in 2 ways, for example, as 72880369 + 53758224 = 8537^2 + 7332^2 .

It is a cyclic number.

It is not a de Polignac number, because 126638593 - 2¹³ = 126630401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126638597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3724648 + ... + 3724681.

It is an arithmetic number, because the mean of its divisors is an integer number (33521985).

Almost surely, 2^126638593 is an apocalyptic number.

It is an amenable number.

126638593 is a deficient number, since it is larger than the sum of its proper divisors (7449347).

126638593 is an equidigital number, since it uses as much as digits as its factorization.

126638593 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7449346.

The product of its digits is 233280, while the sum is 43.

The square root of 126638593 is about 11253.3814029384. The cubic root of 126638593 is about 502.1753129689.

The spelling of 126638593 in words is "one hundred twenty-six million, six hundred thirty-eight thousand, five hundred ninety-three".