668504340 has 240 divisors, whose sum is σ = 2417893632. Its totient is φ = 151455744.

The previous prime is 668504323. The next prime is 668504377. The reversal of 668504340 is 43405866.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 668504295 and 668504304.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1893604 + ... + 1893956.

Almost surely, 2^668504340 is an apocalyptic number.

668504340 is a gapful number since it is divisible by the number (60) 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 668504340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1208946816).

668504340 is an abundant number, since it is smaller than the sum of its proper divisors (1749389292).

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

668504340 is a wasteful number, since it uses less digits than its factorization.

668504340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548 (or 537 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 668504340 is about 25855.4508759758. The cubic root of 668504340 is about 874.3824060962.

The spelling of 668504340 in words is "six hundred sixty-eight million, five hundred four thousand, three hundred forty".