53216660 has 48 divisors (see below), whose sum is σ = 129185280. Its totient is φ = 18036480.

The previous prime is 53216633. The next prime is 53216689. The reversal of 53216660 is 6661235.

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, 10325 + ... + 14595.

It is an arithmetic number, because the mean of its divisors is an integer number (2691360).

Almost surely, 2^53216660 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 53216660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64592640).

53216660 is an abundant number, since it is smaller than the sum of its proper divisors (75968620).

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

53216660 is a wasteful number, since it uses less digits than its factorization.

53216660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4376 (or 4374 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 53216660 is about 7294.9749828221. The cubic root of 53216660 is about 376.1397266267.

Adding to 53216660 its reverse (6661235), we get a palindrome (59877895).

The spelling of 53216660 in words is "fifty-three million, two hundred sixteen thousand, six hundred sixty".