668049408 has 336 divisors, whose sum is σ = 2254169736. Its totient is φ = 188743680.

The previous prime is 668049407. The next prime is 668049413. The reversal of 668049408 is 804940866.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 376049664 + 291999744 = 19392^2 + 17088^2 .

It is a super-3 number, since 3×668049408³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (668049407) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16293868 + ... + 16293908.

Almost surely, 2^668049408 is an apocalyptic number.

668049408 is a gapful number since it is divisible by the number (68) 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 668049408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1127084868).

668049408 is an abundant number, since it is smaller than the sum of its proper divisors (1586120328).

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

668049408 is a wasteful number, since it uses less digits than its factorization.

668049408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The square root of 668049408 is about 25846.6517754234. The cubic root of 668049408 is about 874.1840155594.

The spelling of 668049408 in words is "six hundred sixty-eight million, forty-nine thousand, four hundred eight".