391349487 has 8 divisors (see below), whose sum is σ = 538631680. Its totient is φ = 252483480.

The previous prime is 391349477. The next prime is 391349501. The reversal of 391349487 is 784943193.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-391349487 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391349417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2103937 + ... + 2104122.

It is an arithmetic number, because the mean of its divisors is an integer number (67328960).

Almost surely, 2^391349487 is an apocalyptic number.

391349487 is a deficient number, since it is larger than the sum of its proper divisors (147282193).

391349487 is a wasteful number, since it uses less digits than its factorization.

391349487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4208093.

The product of its digits is 653184, while the sum is 48.

The square root of 391349487 is about 19782.5551180832. Note that the first 3 decimals coincide. The cubic root of 391349487 is about 731.4560835181.

The spelling of 391349487 in words is "three hundred ninety-one million, three hundred forty-nine thousand, four hundred eighty-seven".