391138343 has 4 divisors (see below), whose sum is σ = 391425840. Its totient is φ = 390850848.

The previous prime is 391138327. The next prime is 391138373. The reversal of 391138343 is 343831193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 343831193 = 53 ⋅6487381.

It is a cyclic number.

It is not a de Polignac number, because 391138343 - 2⁴ = 391138327 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 (391138373) 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 3 ways as a sum of consecutive naturals, for example, 141698 + ... + 144431.

It is an arithmetic number, because the mean of its divisors is an integer number (97856460).

Almost surely, 2^391138343 is an apocalyptic number.

391138343 is a deficient number, since it is larger than the sum of its proper divisors (287497).

391138343 is a wasteful number, since it uses less digits than its factorization.

391138343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 287496.

The product of its digits is 23328, while the sum is 35.

The square root of 391138343 is about 19777.2177770282. The cubic root of 391138343 is about 731.3245128444.

The spelling of 391138343 in words is "three hundred ninety-one million, one hundred thirty-eight thousand, three hundred forty-three".