636231680 has 168 divisors, whose sum is σ = 1781749548. Its totient is φ = 217448448.

The previous prime is 636231649. The next prime is 636231683. The reversal of 636231680 is 86132636.

It can be written as a sum of positive squares in 2 ways, for example, as 563777536 + 72454144 = 23744^2 + 8512^2 .

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 636231680.

It is not an unprimeable number, because it can be changed into a prime (636231683) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2006882 + ... + 2007198.

Almost surely, 2^636231680 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 636231680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (890874774).

636231680 is an abundant number, since it is smaller than the sum of its proper divisors (1145517868).

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

636231680 is an equidigital number, since it uses as much as digits as its factorization.

636231680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 362 (or 331 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 636231680 is about 25223.6333623846. The cubic root of 636231680 is about 860.0791706454.

The spelling of 636231680 in words is "six hundred thirty-six million, two hundred thirty-one thousand, six hundred eighty".