316787221 has 4 divisors (see below), whose sum is σ = 318805132. Its totient is φ = 314769312.

The previous prime is 316787203. The next prime is 316787227. The reversal of 316787221 is 122787613.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 185340996 + 131446225 = 13614^2 + 11465^2 .

It is a cyclic number.

It is not a de Polignac number, because 316787221 - 2¹⁷ = 316656149 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 (316787227) 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, 1008720 + ... + 1009033.

It is an arithmetic number, because the mean of its divisors is an integer number (79701283).

Almost surely, 2^316787221 is an apocalyptic number.

It is an amenable number.

316787221 is a deficient number, since it is larger than the sum of its proper divisors (2017911).

316787221 is a wasteful number, since it uses less digits than its factorization.

316787221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2017910.

The product of its digits is 28224, while the sum is 37.

The square root of 316787221 is about 17798.5173820743. The cubic root of 316787221 is about 681.6936021011.

The spelling of 316787221 in words is "three hundred sixteen million, seven hundred eighty-seven thousand, two hundred twenty-one".