637638064 has 80 divisors (see below), whose sum is σ = 1442907648. Its totient is φ = 267342336.

The previous prime is 637638019. The next prime is 637638107. The reversal of 637638064 is 460836736.

It is a self number, because there is not a number n which added to its sum of digits gives 637638064.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1365159 + ... + 1365625.

Almost surely, 2^637638064 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 637638064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (721453824).

637638064 is an abundant number, since it is smaller than the sum of its proper divisors (805269584).

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

637638064 is a wasteful number, since it uses less digits than its factorization.

637638064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 722 (or 716 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 43.

The square root of 637638064 is about 25251.4962724984. The cubic root of 637638064 is about 860.7124365056.

The spelling of 637638064 in words is "six hundred thirty-seven million, six hundred thirty-eight thousand, sixty-four".