391383040 has 96 divisors (see below), whose sum is σ = 965404440. Its totient is φ = 152174592.

The previous prime is 391383023. The next prime is 391383059. The reversal of 391383040 is 40383193.

It can be written as a sum of positive squares in 4 ways, for example, as 389825536 + 1557504 = 19744^2 + 1248^2 .

It is a junction number, because it is equal to n+sod(n) for n = 391382993 and 391383011.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 378364 + ... + 379396.

Almost surely, 2^391383040 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 391383040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (482702220).

391383040 is an abundant number, since it is smaller than the sum of its proper divisors (574021400).

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

391383040 is a wasteful number, since it uses less digits than its factorization.

391383040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1097 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 391383040 is about 19783.4031450608. The cubic root of 391383040 is about 731.4769871225.

The spelling of 391383040 in words is "three hundred ninety-one million, three hundred eighty-three thousand, forty".