394616728987 has 4 divisors (see below), whose sum is σ = 424971862000. Its totient is φ = 364261595976.

The previous prime is 394616728973. The next prime is 394616729009. The reversal of 394616728987 is 789827616493.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 394616728987 - 2³¹ = 392469245339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (394616728907) 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, 15177566487 + ... + 15177566512.

It is an arithmetic number, because the mean of its divisors is an integer number (106242965500).

Almost surely, 2^394616728987 is an apocalyptic number.

394616728987 is a deficient number, since it is larger than the sum of its proper divisors (30355133013).

394616728987 is a wasteful number, since it uses less digits than its factorization.

394616728987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30355133012.

The product of its digits is 219469824, while the sum is 70.

The spelling of 394616728987 in words is "three hundred ninety-four billion, six hundred sixteen million, seven hundred twenty-eight thousand, nine hundred eighty-seven".