6561035220 has 48 divisors (see below), whose sum is σ = 18374444928. Its totient is φ = 1749271680.

The previous prime is 6561035191. The next prime is 6561035263. The reversal of 6561035220 is 225301656.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 541630 + ... + 553610.

It is an arithmetic number, because the mean of its divisors is an integer number (382800936).

Almost surely, 2^6561035220 is an apocalyptic number.

6561035220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6561035220 is an abundant number, since it is smaller than the sum of its proper divisors (11813409708).

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

6561035220 is a wasteful number, since it uses less digits than its factorization.

6561035220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21120 (or 21118 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 6561035220 is about 81000.2174071156. The cubic root of 6561035220 is about 1872.0787905602.

Adding to 6561035220 its reverse (225301656), we get a palindrome (6786336876).

The spelling of 6561035220 in words is "six billion, five hundred sixty-one million, thirty-five thousand, two hundred twenty".