221520322001 has 16 divisors (see below), whose sum is σ = 246467225088. Its totient is φ = 197382556800.

The previous prime is 221520321937. The next prime is 221520322039. The reversal of 221520322001 is 100223025122.

It is not a de Polignac number, because 221520322001 - 2⁶ = 221520321937 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221520322081) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 386045 + ... + 769461.

It is an arithmetic number, because the mean of its divisors is an integer number (15404201568).

Almost surely, 2^221520322001 is an apocalyptic number.

It is an amenable number.

221520322001 is a deficient number, since it is larger than the sum of its proper divisors (24946903087).

221520322001 is a wasteful number, since it uses less digits than its factorization.

221520322001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384472.

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 221520322001 its reverse (100223025122), we get a palindrome (321743347123).

The spelling of 221520322001 in words is "two hundred twenty-one billion, five hundred twenty million, three hundred twenty-two thousand, one".