391103261 has 4 divisors (see below), whose sum is σ = 391502112. Its totient is φ = 390704412.

The previous prime is 391103243. The next prime is 391103281. The reversal of 391103261 is 162301193.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 162301193 = 17 ⋅9547129.

It is a cyclic number.

It is not a de Polignac number, because 391103261 - 2²⁶ = 323994397 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 391103261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391103281) 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 3 ways as a sum of consecutive naturals, for example, 197951 + ... + 199916.

It is an arithmetic number, because the mean of its divisors is an integer number (97875528).

Almost surely, 2^391103261 is an apocalyptic number.

It is an amenable number.

391103261 is a deficient number, since it is larger than the sum of its proper divisors (398851).

391103261 is an equidigital number, since it uses as much as digits as its factorization.

391103261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 398850.

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

The square root of 391103261 is about 19776.3308275322. The cubic root of 391103261 is about 731.3026475256.

The spelling of 391103261 in words is "three hundred ninety-one million, one hundred three thousand, two hundred sixty-one".