391580091 has 48 divisors (see below), whose sum is σ = 689914368. Its totient is φ = 208915200.

The previous prime is 391580081. The next prime is 391580117. The reversal of 391580091 is 190085193.

It is a happy number.

It is not a de Polignac number, because 391580091 - 2⁹ = 391579579 is a prime.

It is not an unprimeable number, because it can be changed into a prime (391580041) 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 47 ways as a sum of consecutive naturals, for example, 138906 + ... + 141696.

It is an arithmetic number, because the mean of its divisors is an integer number (14373216).

Almost surely, 2^391580091 is an apocalyptic number.

391580091 is a deficient number, since it is larger than the sum of its proper divisors (298334277).

391580091 is a wasteful number, since it uses less digits than its factorization.

391580091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2952 (or 2949 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 391580091 is about 19788.3827282575. The cubic root of 391580091 is about 731.5997262927.

The spelling of 391580091 in words is "three hundred ninety-one million, five hundred eighty thousand, ninety-one".