391531284473 has 6 divisors (see below), whose sum is σ = 455454759546. Its totient is φ = 335598243792.

The previous prime is 391531284439. The next prime is 391531284491. The reversal of 391531284473 is 374482135193.

It can be written as a sum of positive squares in only one way, i.e., 391108899769 + 422384704 = 625387^2 + 20552^2 .

It is not a de Polignac number, because 391531284473 - 2⁸ = 391531284217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (391531281473) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3995217140 + ... + 3995217237.

It is an arithmetic number, because the mean of its divisors is an integer number (75909126591).

Almost surely, 2^391531284473 is an apocalyptic number.

It is an amenable number.

391531284473 is a deficient number, since it is larger than the sum of its proper divisors (63923475073).

391531284473 is an equidigital number, since it uses as much as digits as its factorization.

391531284473 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7990434391 (or 7990434384 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 50.

The spelling of 391531284473 in words is "three hundred ninety-one billion, five hundred thirty-one million, two hundred eighty-four thousand, four hundred seventy-three".