221620315 has 8 divisors (see below), whose sum is σ = 303936480. Its totient is φ = 151968192.

The previous prime is 221620297. The next prime is 221620337. The reversal of 221620315 is 513026122.

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

It is a cyclic number.

It is not a de Polignac number, because 221620315 - 2⁷ = 221620187 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3165970 + ... + 3166039.

It is an arithmetic number, because the mean of its divisors is an integer number (37992060).

Almost surely, 2^221620315 is an apocalyptic number.

221620315 is a deficient number, since it is larger than the sum of its proper divisors (82316165).

221620315 is an equidigital number, since it uses as much as digits as its factorization.

221620315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6332021.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 221620315 is about 14886.9175788677. The cubic root of 221620315 is about 605.1595007822.

Adding to 221620315 its reverse (513026122), we get a palindrome (734646437).

The spelling of 221620315 in words is "two hundred twenty-one million, six hundred twenty thousand, three hundred fifteen".