668748924 has 72 divisors (see below), whose sum is σ = 1807434720. Its totient is φ = 207766656.

The previous prime is 668748901. The next prime is 668748953. The reversal of 668748924 is 429847866.

668748924 is a `hidden beast` number, since 66 + 87 + 489 + 24 = 666.

Its product of digits (4644864) is a multiple of the sum of its prime factors (336).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6492657 + ... + 6492759.

It is an arithmetic number, because the mean of its divisors is an integer number (25103260).

Almost surely, 2^668748924 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 668748924, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (903717360).

668748924 is an abundant number, since it is smaller than the sum of its proper divisors (1138685796).

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

668748924 is a wasteful number, since it uses less digits than its factorization.

668748924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336 (or 125 counting only the distinct ones).

The product of its digits is 4644864, while the sum is 54.

The square root of 668748924 is about 25860.1802777939. The cubic root of 668748924 is about 874.4890291239.

It can be divided in two parts, 6687 and 48924, that added together give a triangular number (55611 = T₃₃₃).

The spelling of 668748924 in words is "six hundred sixty-eight million, seven hundred forty-eight thousand, nine hundred twenty-four".