391045491 has 12 divisors (see below), whose sum is σ = 566663760. Its totient is φ = 259856880.

The previous prime is 391045463. The next prime is 391045507. The reversal of 391045491 is 194540193.

It is a happy number.

391045491 is a `hidden beast` number, since 3 + 9 + 104 + 549 + 1 = 666.

It is not a de Polignac number, because 391045491 - 2¹⁹ = 390521203 is a prime.

It is not an unprimeable number, because it can be changed into a prime (391045891) 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 11 ways as a sum of consecutive naturals, for example, 67056 + ... + 72653.

It is an arithmetic number, because the mean of its divisors is an integer number (47221980).

Almost surely, 2^391045491 is an apocalyptic number.

391045491 is a deficient number, since it is larger than the sum of its proper divisors (175618269).

391045491 is a wasteful number, since it uses less digits than its factorization.

391045491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140026 (or 140023 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 391045491 is about 19774.8701892073. The cubic root of 391045491 is about 731.2666387623.

The spelling of 391045491 in words is "three hundred ninety-one million, forty-five thousand, four hundred ninety-one".