126218436217 has 4 divisors (see below), whose sum is σ = 126220932196. Its totient is φ = 126215940240.

The previous prime is 126218436209. The next prime is 126218436257. The reversal of 126218436217 is 712634812621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 712634812621 = 374203 ⋅1904407.

It can be written as a sum of positive squares in 2 ways, for example, as 55974354921 + 70244081296 = 236589^2 + 265036^2 .

It is a cyclic number.

It is not a de Polignac number, because 126218436217 - 2³ = 126218436209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126218436257) 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, 1170534 + ... + 1273807.

It is an arithmetic number, because the mean of its divisors is an integer number (31555233049).

Almost surely, 2^126218436217 is an apocalyptic number.

It is an amenable number.

126218436217 is a deficient number, since it is larger than the sum of its proper divisors (2495979).

126218436217 is an equidigital number, since it uses as much as digits as its factorization.

126218436217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2495978.

The product of its digits is 193536, while the sum is 43.

The spelling of 126218436217 in words is "one hundred twenty-six billion, two hundred eighteen million, four hundred thirty-six thousand, two hundred seventeen".