668981154240 has 336 divisors, whose sum is σ = 2654318564352. Its totient is φ = 151480424448.

The previous prime is 668981154211. The next prime is 668981154263. The reversal of 668981154240 is 42451189866.

668981154240 is a `hidden beast` number, since 6 + 6 + 8 + 98 + 1 + 1 + 542 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2002057 + ... + 2312183.

It is an arithmetic number, because the mean of its divisors is an integer number (7899757632).

Almost surely, 2^668981154240 is an apocalyptic number.

668981154240 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 668981154240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1327159282176).

668981154240 is an abundant number, since it is smaller than the sum of its proper divisors (1985337410112).

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

668981154240 is a wasteful number, since it uses less digits than its factorization.

668981154240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310264 (or 310251 counting only the distinct ones).

The product of its (nonzero) digits is 3317760, while the sum is 54.

The spelling of 668981154240 in words is "six hundred sixty-eight billion, nine hundred eighty-one million, one hundred fifty-four thousand, two hundred forty".