2168399904 has 96 divisors (see below), whose sum is σ = 6409912320. Its totient is φ = 635884800.

The previous prime is 2168399903. The next prime is 2168399939. The reversal of 2168399904 is 4099938612.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (2168399903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 384 + ... + 65855.

It is an arithmetic number, because the mean of its divisors is an integer number (66769920).

Almost surely, 2^2168399904 is an apocalyptic number.

2168399904 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2168399904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3204956160).

2168399904 is an abundant number, since it is smaller than the sum of its proper divisors (4241512416).

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

2168399904 is a wasteful number, since it uses less digits than its factorization.

2168399904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66294 (or 66286 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 51.

The square root of 2168399904 is about 46566.0810461864. The cubic root of 2168399904 is about 1294.3342988578.

The spelling of 2168399904 in words is "two billion, one hundred sixty-eight million, three hundred ninety-nine thousand, nine hundred four".