64163939840 has 800 divisors, whose sum is σ = 213737632416. Its totient is φ = 18207866880.

The previous prime is 64163939837. The next prime is 64163939849. The reversal of 64163939840 is 4893936146.

It is a super-2 number, since 2×64163939840² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64163939849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 878958044 + ... + 878958116.

Almost surely, 2^64163939840 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 64163939840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106868816208).

64163939840 is an abundant number, since it is smaller than the sum of its proper divisors (149573692576).

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

64163939840 is an equidigital number, since it uses as much as digits as its factorization.

64163939840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 53.

The spelling of 64163939840 in words is "sixty-four billion, one hundred sixty-three million, nine hundred thirty-nine thousand, eight hundred forty".