668521296 has 80 divisors (see below), whose sum is σ = 1933715520. Its totient is φ = 221120640.

The previous prime is 668521283. The next prime is 668521297. The reversal of 668521296 is 692125866.

668521296 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (668521297) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50686 + ... + 62498.

It is an arithmetic number, because the mean of its divisors is an integer number (24171444).

Almost surely, 2^668521296 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 668521296, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (966857760).

668521296 is an abundant number, since it is smaller than the sum of its proper divisors (1265194224).

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

668521296 is a wasteful number, since it uses less digits than its factorization.

668521296 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11961 (or 11949 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 668521296 is about 25855.7787738061. The cubic root of 668521296 is about 874.3897986699.

The spelling of 668521296 in words is "six hundred sixty-eight million, five hundred twenty-one thousand, two hundred ninety-six".