391662750091 has 8 divisors (see below), whose sum is σ = 404576482304. Its totient is φ = 378766483560.

The previous prime is 391662750067. The next prime is 391662750103. The reversal of 391662750091 is 190057266193.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 391662750091 - 2²¹ = 391660652939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (391662751091) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4320825 + ... + 4410538.

It is an arithmetic number, because the mean of its divisors is an integer number (50572060288).

Almost surely, 2^391662750091 is an apocalyptic number.

391662750091 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

391662750091 is a deficient number, since it is larger than the sum of its proper divisors (12913732213).

391662750091 is a wasteful number, since it uses less digits than its factorization.

391662750091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8732841.

The product of its (nonzero) digits is 612360, while the sum is 49.

The spelling of 391662750091 in words is "three hundred ninety-one billion, six hundred sixty-two million, seven hundred fifty thousand, ninety-one".