123939009 has 6 divisors (see below), whose sum is σ = 179023026. Its totient is φ = 82626000.

The previous prime is 123938989. The next prime is 123939017. The reversal of 123939009 is 900939321.

It can be written as a sum of positive squares in only one way, i.e., 76947984 + 46991025 = 8772^2 + 6855^2 .

It is not a de Polignac number, because 123939009 - 2⁸ = 123938753 is a prime.

It is not an unprimeable number, because it can be changed into a prime (123939059) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6885492 + ... + 6885509.

It is an arithmetic number, because the mean of its divisors is an integer number (29837171).

Almost surely, 2^123939009 is an apocalyptic number.

It is an amenable number.

123939009 is a deficient number, since it is larger than the sum of its proper divisors (55084017).

123939009 is a wasteful number, since it uses less digits than its factorization.

123939009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13771007 (or 13771004 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 36.

The square root of 123939009 is about 11132.7898120821. The cubic root of 123939009 is about 498.5813238564.

The spelling of 123939009 in words is "one hundred twenty-three million, nine hundred thirty-nine thousand, nine".