123939217 has 4 divisors (see below), whose sum is σ = 124681536. Its totient is φ = 123196900.

The previous prime is 123939199. The next prime is 123939239. The reversal of 123939217 is 712939321.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 712939321 = 12269 ⋅58109.

It is a cyclic number.

It is not a de Polignac number, because 123939217 - 2⁷ = 123939089 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123939247) 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 3 ways as a sum of consecutive naturals, for example, 370909 + ... + 371242.

It is an arithmetic number, because the mean of its divisors is an integer number (31170384).

Almost surely, 2^123939217 is an apocalyptic number.

It is an amenable number.

123939217 is a deficient number, since it is larger than the sum of its proper divisors (742319).

123939217 is an equidigital number, since it uses as much as digits as its factorization.

123939217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 742318.

The product of its digits is 20412, while the sum is 37.

The square root of 123939217 is about 11132.7991538516. The cubic root of 123939217 is about 498.5816027701.

The spelling of 123939217 in words is "one hundred twenty-three million, nine hundred thirty-nine thousand, two hundred seventeen".