64815120000 has 640 divisors, whose sum is σ = 245805067200. Its totient is φ = 16796160000.

The previous prime is 64815119987. The next prime is 64815120043. The reversal of 64815120000 is 2151846.

64815120000 is a `hidden beast` number, since 648 + 1 + 5 + 12 + 0 + 0 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a super-2 number, since 2×64815120000² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 79919595 + ... + 79920405.

Almost surely, 2^64815120000 is an apocalyptic number.

64815120000 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 64815120000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122902533600).

64815120000 is an abundant number, since it is smaller than the sum of its proper divisors (180989947200).

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

64815120000 is an equidigital number, since it uses as much as digits as its factorization.

64815120000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 891 (or 858 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

Adding to 64815120000 its reverse (2151846), we get a palindrome (64817271846).

The spelling of 64815120000 in words is "sixty-four billion, eight hundred fifteen million, one hundred twenty thousand".