393974845520 has 40 divisors (see below), whose sum is σ = 922139137800. Its totient is φ = 156532282880.

The previous prime is 393974845513. The next prime is 393974845541. The reversal of 393974845520 is 25548479393.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6503454736 + 387471390784 = 80644^2 + 622472^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 393974845520.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16513871 + ... + 16537710.

It is an arithmetic number, because the mean of its divisors is an integer number (23053478445).

Almost surely, 2^393974845520 is an apocalyptic number.

It is an amenable number.

393974845520 is an abundant number, since it is smaller than the sum of its proper divisors (528164292280).

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

393974845520 is a wasteful number, since it uses less digits than its factorization.

393974845520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33051743 (or 33051737 counting only the distinct ones).

The product of its (nonzero) digits is 32659200, while the sum is 59.

The spelling of 393974845520 in words is "three hundred ninety-three billion, nine hundred seventy-four million, eight hundred forty-five thousand, five hundred twenty".