221520147 has 8 divisors (see below), whose sum is σ = 303343056. Its totient is φ = 143688672.

The previous prime is 221520137. The next prime is 221520151. The reversal of 221520147 is 741025122.

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

It is not a de Polignac number, because 221520147 - 2²⁰ = 220471571 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221520137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 997728 + ... + 997949.

It is an arithmetic number, because the mean of its divisors is an integer number (37917882).

Almost surely, 2^221520147 is an apocalyptic number.

221520147 is a deficient number, since it is larger than the sum of its proper divisors (81822909).

221520147 is a wasteful number, since it uses less digits than its factorization.

221520147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1995717.

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 221520147 is about 14883.5529024491. The cubic root of 221520147 is about 605.0683136667.

Adding to 221520147 its reverse (741025122), we get a palindrome (962545269).

The spelling of 221520147 in words is "two hundred twenty-one million, five hundred twenty thousand, one hundred forty-seven".