221645513 has 8 divisors (see below), whose sum is σ = 225539136. Its totient is φ = 217760400.

The previous prime is 221645491. The next prime is 221645519. The reversal of 221645513 is 315546122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221645513 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (221645519) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73118 + ... + 76088.

It is an arithmetic number, because the mean of its divisors is an integer number (28192392).

Almost surely, 2^221645513 is an apocalyptic number.

It is an amenable number.

221645513 is a deficient number, since it is larger than the sum of its proper divisors (3893623).

221645513 is a wasteful number, since it uses less digits than its factorization.

221645513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4255.

The product of its digits is 7200, while the sum is 29.

The square root of 221645513 is about 14887.7638683585. The cubic root of 221645513 is about 605.1824352489.

The spelling of 221645513 in words is "two hundred twenty-one million, six hundred forty-five thousand, five hundred thirteen".