399326907039744 has 128 divisors (see below), whose sum is σ = 1070430713487360. Its totient is φ = 132412057190400.

The previous prime is 399326907039743. The next prime is 399326907039761. The reversal of 399326907039744 is 447930709623993.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399326907039743) by changing a digit.

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, 8142129 + ... + 29409999.

It is an arithmetic number, because the mean of its divisors is an integer number (8362739949120).

Almost surely, 2^{399326907039744} 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 399326907039744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (535215356743680).

399326907039744 is an abundant number, since it is smaller than the sum of its proper divisors (671103806447616).

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

399326907039744 is an equidigital number, since it uses as much as digits as its factorization.

399326907039744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21268095 (or 21268067 counting only the distinct ones).

The product of its (nonzero) digits is 1666598976, while the sum is 75.

The spelling of 399326907039744 in words is "three hundred ninety-nine trillion, three hundred twenty-six billion, nine hundred seven million, thirty-nine thousand, seven hundred forty-four".