6538961520 has 600 divisors, whose sum is σ = 28138261536. Its totient is φ = 1378031616.

The previous prime is 6538961503. The next prime is 6538961521. The reversal of 6538961520 is 251698356.

6538961520 is a `hidden beast` number, since 6 + 5 + 3 + 8 + 9 + 615 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6538961521) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 7665414 + ... + 7666266.

Almost surely, 2^6538961520 is an apocalyptic number.

6538961520 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 6538961520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14069130768).

6538961520 is an abundant number, since it is smaller than the sum of its proper divisors (21599300016).

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

6538961520 is a wasteful number, since it uses less digits than its factorization.

6538961520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911 (or 883 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The square root of 6538961520 is about 80863.8455677196. The cubic root of 6538961520 is about 1869.9769812336.

The spelling of 6538961520 in words is "six billion, five hundred thirty-eight million, nine hundred sixty-one thousand, five hundred twenty".