391785044040 has 192 divisors, whose sum is σ = 1393728139440. Its totient is φ = 94858352640.

The previous prime is 391785044033. The next prime is 391785044041. The reversal of 391785044040 is 40440587193.

391785044040 is a `hidden beast` number, since 3 + 91 + 7 + 85 + 0 + 440 + 40 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 10698592356 + 381086451684 = 103434^2 + 617322^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (391785044041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 400707 + ... + 971666.

Almost surely, 2^391785044040 is an apocalyptic number.

391785044040 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

391785044040 is an abundant number, since it is smaller than the sum of its proper divisors (1001943095400).

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

391785044040 is a wasteful number, since it uses less digits than its factorization.

391785044040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1372464 (or 1372457 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 391785044040 in words is "three hundred ninety-one billion, seven hundred eighty-five million, forty-four thousand, forty".