221366516 has 36 divisors (see below), whose sum is σ = 453404448. Its totient is φ = 94289328.

The previous prime is 221366501. The next prime is 221366539. The reversal of 221366516 is 615663122.

221366516 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29351 + ... + 36113.

It is an arithmetic number, because the mean of its divisors is an integer number (12594568).

Almost surely, 2^221366516 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 221366516, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (226702224).

221366516 is an abundant number, since it is smaller than the sum of its proper divisors (232037932).

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

221366516 is a wasteful number, since it uses less digits than its factorization.

221366516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6948 (or 6939 counting only the distinct ones).

The product of its digits is 12960, while the sum is 32.

The square root of 221366516 is about 14878.3909076217. The cubic root of 221366516 is about 604.9284035212.

The spelling of 221366516 in words is "two hundred twenty-one million, three hundred sixty-six thousand, five hundred sixteen".