12123472509 has 6 divisors (see below), whose sum is σ = 17511682526. Its totient is φ = 8082315000.

The previous prime is 12123472489. The next prime is 12123472547. The reversal of 12123472509 is 90527432121.

12123472509 is a `hidden beast` number, since 12 + 123 + 472 + 50 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 11825910009 + 297562500 = 108747^2 + 17250^2 .

It is not a de Polignac number, because 12123472509 - 2¹³ = 12123464317 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12123472549) 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, 673526242 + ... + 673526259.

Almost surely, 2^12123472509 is an apocalyptic number.

It is an amenable number.

12123472509 is a deficient number, since it is larger than the sum of its proper divisors (5388210017).

12123472509 is a wasteful number, since it uses less digits than its factorization.

12123472509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1347052507 (or 1347052504 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The spelling of 12123472509 in words is "twelve billion, one hundred twenty-three million, four hundred seventy-two thousand, five hundred nine".