391205097 has 12 divisors (see below), whose sum is σ = 565352580. Its totient is φ = 260674848.

The previous prime is 391205093. The next prime is 391205123. The reversal of 391205097 is 790502193.

It can be written as a sum of positive squares in 2 ways, for example, as 14107536 + 377097561 = 3756^2 + 19419^2 .

It is not a de Polignac number, because 391205097 - 2² = 391205093 is a prime.

It is not an unprimeable number, because it can be changed into a prime (391205093) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10843 + ... + 29999.

It is an arithmetic number, because the mean of its divisors is an integer number (47112715).

Almost surely, 2^391205097 is an apocalyptic number.

It is an amenable number.

391205097 is a deficient number, since it is larger than the sum of its proper divisors (174147483).

391205097 is a wasteful number, since it uses less digits than its factorization.

391205097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21432 (or 21429 counting only the distinct ones).

The product of its (nonzero) digits is 17010, while the sum is 36.

The square root of 391205097 is about 19778.9053539371. The cubic root of 391205097 is about 731.3661145440.

The spelling of 391205097 in words is "three hundred ninety-one million, two hundred five thousand, ninety-seven".