391338216 has 40 divisors (see below), whose sum is σ = 1096111170. Its totient is φ = 130445856.

The previous prime is 391338197. The next prime is 391338221. The reversal of 391338216 is 612833193.

It can be written as a sum of positive squares in only one way, i.e., 260693316 + 130644900 = 16146^2 + 11430^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 301311 + ... + 302606.

Almost surely, 2^391338216 is an apocalyptic number.

391338216 is a gapful number since it is divisible by the number (36) formed by its first and last digit.

It is an amenable number.

391338216 is an abundant number, since it is smaller than the sum of its proper divisors (704772954).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

391338216 is a wasteful number, since it uses less digits than its factorization.

391338216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 603935 (or 603922 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 391338216 is about 19782.2702438320. The cubic root of 391338216 is about 731.4490613883.

The spelling of 391338216 in words is "three hundred ninety-one million, three hundred thirty-eight thousand, two hundred sixteen".