391448478 has 16 divisors (see below), whose sum is σ = 786318480. Its totient is φ = 129912576.

The previous prime is 391448471. The next prime is 391448483. The reversal of 391448478 is 874844193.

It is a super-3 number, since 3×391448478³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391448471) 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, 141075 + ... + 143822.

It is an arithmetic number, because the mean of its divisors is an integer number (49144905).

Almost surely, 2^391448478 is an apocalyptic number.

391448478 is an abundant number, since it is smaller than the sum of its proper divisors (394870002).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

391448478 is a wasteful number, since it uses less digits than its factorization.

391448478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285131.

The product of its digits is 774144, while the sum is 48.

The square root of 391448478 is about 19785.0569369916. The cubic root of 391448478 is about 731.5177517263.

The spelling of 391448478 in words is "three hundred ninety-one million, four hundred forty-eight thousand, four hundred seventy-eight".