391489099 has 4 divisors (see below), whose sum is σ = 391609960. Its totient is φ = 391368240.

The previous prime is 391489097. The next prime is 391489103. The reversal of 391489099 is 990984193.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 990984193 = 15361 ⋅64513.

It is a cyclic number.

It is not a de Polignac number, because 391489099 - 2¹ = 391489097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (391489097) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55434 + ... + 62095.

It is an arithmetic number, because the mean of its divisors is an integer number (97902490).

Almost surely, 2^391489099 is an apocalyptic number.

391489099 is a deficient number, since it is larger than the sum of its proper divisors (120861).

391489099 is a wasteful number, since it uses less digits than its factorization.

391489099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120860.

The product of its (nonzero) digits is 629856, while the sum is 52.

The square root of 391489099 is about 19786.0834679327. The cubic root of 391489099 is about 731.5430542939.

The spelling of 391489099 in words is "three hundred ninety-one million, four hundred eighty-nine thousand, ninety-nine".