221216001 has 8 divisors (see below), whose sum is σ = 307778880. Its totient is φ = 141065232.

The previous prime is 221215991. The next prime is 221216003. The reversal of 221216001 is 100612122.

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

It is not a de Polignac number, because 221216001 - 2⁶ = 221215937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221216003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1602946 + ... + 1603083.

It is an arithmetic number, because the mean of its divisors is an integer number (38472360).

Almost surely, 2^221216001 is an apocalyptic number.

It is an amenable number.

221216001 is a deficient number, since it is larger than the sum of its proper divisors (86562879).

221216001 is a wasteful number, since it uses less digits than its factorization.

221216001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3206055.

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 221216001 is about 14873.3318728522. The cubic root of 221216001 is about 604.7912682936.

Adding to 221216001 its reverse (100612122), we get a palindrome (321828123).

The spelling of 221216001 in words is "two hundred twenty-one million, two hundred sixteen thousand, one".