208664216640 has 672 divisors, whose sum is σ = 821386500480. Its totient is φ = 49998643200.

The previous prime is 208664216639. The next prime is 208664216641. The reversal of 208664216640 is 46612466802.

It is an interprime number because it is at equal distance from previous prime (208664216639) and next prime (208664216641).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (208664216641) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 76125670 + ... + 76128410.

It is an arithmetic number, because the mean of its divisors is an integer number (1222301340).

Almost surely, 2^208664216640 is an apocalyptic number.

208664216640 is a gapful number since it is divisible by the number (20) 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 208664216640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (410693250240).

208664216640 is an abundant number, since it is smaller than the sum of its proper divisors (612722283840).

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

208664216640 is a wasteful number, since it uses less digits than its factorization.

208664216640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2873 (or 2851 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 45.

The spelling of 208664216640 in words is "two hundred eight billion, six hundred sixty-four million, two hundred sixteen thousand, six hundred forty".