6501618720 has 288 divisors, whose sum is σ = 23590148400. Its totient is φ = 1624965120.

The previous prime is 6501618707. The next prime is 6501618731. The reversal of 6501618720 is 278161056.

It can be written as a sum of positive squares in 8 ways, for example, as 2175662736 + 4325955984 = 46644^2 + 65772^2 .

It is a tau number, because it is divible by the number of its divisors (288).

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8543140 + ... + 8543900.

Almost surely, 2^6501618720 is an apocalyptic number.

6501618720 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 6501618720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11795074200).

6501618720 is an abundant number, since it is smaller than the sum of its proper divisors (17088529680).

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

6501618720 is a wasteful number, since it uses less digits than its factorization.

6501618720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1148 (or 1137 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 6501618720 is about 80632.6157333371. The cubic root of 6501618720 is about 1866.4104858185.

Adding to 6501618720 its reverse (278161056), we get a palindrome (6779779776).

The spelling of 6501618720 in words is "six billion, five hundred one million, six hundred eighteen thousand, seven hundred twenty".