399341729664 has 128 divisors (see below), whose sum is σ = 1178947008000. Its totient is φ = 133076160000.

The previous prime is 399341729629. The next prime is 399341729693. The reversal of 399341729664 is 466927143993.

399341729664 is a `hidden beast` number, since 399 + 34 + 1 + 72 + 96 + 64 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13875289 + ... + 13904039.

It is an arithmetic number, because the mean of its divisors is an integer number (9210523500).

Almost surely, 2^399341729664 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 399341729664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (589473504000).

399341729664 is an abundant number, since it is smaller than the sum of its proper divisors (779605278336).

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

399341729664 is a wasteful number, since it uses less digits than its factorization.

399341729664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32793 (or 32775 counting only the distinct ones).

The product of its digits is 52907904, while the sum is 63.

The spelling of 399341729664 in words is "three hundred ninety-nine billion, three hundred forty-one million, seven hundred twenty-nine thousand, six hundred sixty-four".