391311143 has 4 divisors (see below), whose sum is σ = 399636960. Its totient is φ = 382985328.

The previous prime is 391311131. The next prime is 391311161. The reversal of 391311143 is 341113193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 341113193 = 5059 ⋅67427.

It is not a de Polignac number, because 391311143 - 2⁶ = 391311079 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 (391311113) 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, 4162838 + ... + 4162931.

It is an arithmetic number, because the mean of its divisors is an integer number (99909240).

Almost surely, 2^391311143 is an apocalyptic number.

391311143 is a deficient number, since it is larger than the sum of its proper divisors (8325817).

391311143 is an equidigital number, since it uses as much as digits as its factorization.

391311143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8325816.

The product of its digits is 972, while the sum is 26.

The square root of 391311143 is about 19781.5859576526. The cubic root of 391311143 is about 731.4321936455.

The spelling of 391311143 in words is "three hundred ninety-one million, three hundred eleven thousand, one hundred forty-three".