68657220 has 168 divisors, whose sum is σ = 229713624. Its totient is φ = 17169408.

The previous prime is 68657161. The next prime is 68657221. The reversal of 68657220 is 2275686.

68657220 is a `hidden beast` number, since 6 + 86 + 572 + 2 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 5645376 + 63011844 = 2376^2 + 7938^2 .

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

It is not an unprimeable number, because it can be changed into a prime (68657221) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 247722 + ... + 247998.

It is an arithmetic number, because the mean of its divisors is an integer number (1367343).

Almost surely, 2^68657220 is an apocalyptic number.

68657220 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 68657220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114856812).

68657220 is an abundant number, since it is smaller than the sum of its proper divisors (161056404).

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

68657220 is a wasteful number, since it uses less digits than its factorization.

68657220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 68657220 is about 8285.9652425049. The cubic root of 68657220 is about 409.4762696066.

The spelling of 68657220 in words is "sixty-eight million, six hundred fifty-seven thousand, two hundred twenty".