391734913 has 4 divisors (see below), whose sum is σ = 412352560. Its totient is φ = 371117268.

The previous prime is 391734907. The next prime is 391734949. The reversal of 391734913 is 319437193.

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: 319437193 = 7321 ⋅43633.

It is a cyclic number.

It is not a de Polignac number, because 391734913 - 2⁵ = 391734881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (391734113) 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, 10308795 + ... + 10308832.

It is an arithmetic number, because the mean of its divisors is an integer number (103088140).

Almost surely, 2^391734913 is an apocalyptic number.

It is an amenable number.

391734913 is a deficient number, since it is larger than the sum of its proper divisors (20617647).

391734913 is a wasteful number, since it uses less digits than its factorization.

391734913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20617646.

The product of its digits is 61236, while the sum is 40.

The square root of 391734913 is about 19792.2942833821. The cubic root of 391734913 is about 731.6961329715.

The spelling of 391734913 in words is "three hundred ninety-one million, seven hundred thirty-four thousand, nine hundred thirteen".