391678983 has 20 divisors (see below), whose sum is σ = 610542768. Its totient is φ = 249765120.

The previous prime is 391678981. The next prime is 391678999. The reversal of 391678983 is 389876193.

It is not a de Polignac number, because 391678983 - 2¹ = 391678981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391678981) 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 19 ways as a sum of consecutive naturals, for example, 103258 + ... + 106983.

Almost surely, 2^391678983 is an apocalyptic number.

391678983 is a deficient number, since it is larger than the sum of its proper divisors (218863785).

391678983 is a wasteful number, since it uses less digits than its factorization.

391678983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210276 (or 210267 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 54.

The square root of 391678983 is about 19790.8813093303. The cubic root of 391678983 is about 731.6613086459.

The spelling of 391678983 in words is "three hundred ninety-one million, six hundred seventy-eight thousand, nine hundred eighty-three".