126123817 has 4 divisors (see below), whose sum is σ = 126214740. Its totient is φ = 126032896.

The previous prime is 126123797. The next prime is 126123847. The reversal of 126123817 is 718321621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 718321621 = 17 ⋅42254213.

It can be written as a sum of positive squares in 2 ways, for example, as 17464041 + 108659776 = 4179^2 + 10424^2 .

It is a cyclic number.

It is not a de Polignac number, because 126123817 - 2⁷ = 126123689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126123847) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43348 + ... + 46165.

It is an arithmetic number, because the mean of its divisors is an integer number (31553685).

Almost surely, 2^126123817 is an apocalyptic number.

It is an amenable number.

126123817 is a deficient number, since it is larger than the sum of its proper divisors (90923).

126123817 is an equidigital number, since it uses as much as digits as its factorization.

126123817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90922.

The product of its digits is 4032, while the sum is 31.

The square root of 126123817 is about 11230.4860535954. The cubic root of 126123817 is about 501.4939544212.

The spelling of 126123817 in words is "one hundred twenty-six million, one hundred twenty-three thousand, eight hundred seventeen".