393129689 has 8 divisors (see below), whose sum is σ = 409322760. Its totient is φ = 377251200.

The previous prime is 393129637. The next prime is 393129697. The reversal of 393129689 is 986921393.

It can be written as a sum of positive squares in 4 ways, for example, as 13542400 + 379587289 = 3680^2 + 19483^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 393129689 - 2²⁰ = 392081113 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (393129889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76094 + ... + 81095.

It is an arithmetic number, because the mean of its divisors is an integer number (51165345).

Almost surely, 2^393129689 is an apocalyptic number.

It is an amenable number.

393129689 is a deficient number, since it is larger than the sum of its proper divisors (16193071).

393129689 is a wasteful number, since it uses less digits than its factorization.

393129689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 157291.

The product of its digits is 629856, while the sum is 50.

The square root of 393129689 is about 19827.4983041230. The cubic root of 393129689 is about 732.5635081048.

The spelling of 393129689 in words is "three hundred ninety-three million, one hundred twenty-nine thousand, six hundred eighty-nine".