668680154820 has 48 divisors (see below), whose sum is σ = 2080338261120. Its totient is φ = 178314707808.

The previous prime is 668680154777. The next prime is 668680154861. The reversal of 668680154820 is 28451086866.

668680154820 is a `hidden beast` number, since 6 + 6 + 86 + 80 + 1 + 5 + 482 + 0 = 666.

668680154820 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 619147752 + ... + 619148831.

It is an arithmetic number, because the mean of its divisors is an integer number (43340380440).

Almost surely, 2^668680154820 is an apocalyptic number.

668680154820 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

668680154820 is an abundant number, since it is smaller than the sum of its proper divisors (1411658106300).

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

668680154820 is a wasteful number, since it uses less digits than its factorization.

668680154820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1238296601 (or 1238296593 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 54.

The spelling of 668680154820 in words is "six hundred sixty-eight billion, six hundred eighty million, one hundred fifty-four thousand, eight hundred twenty".