221210211001 has 16 divisors (see below), whose sum is σ = 254080898064. Its totient is φ = 190779807744.

The previous prime is 221210210989. The next prime is 221210211007. The reversal of 221210211001 is 100112012122.

It can be written as a sum of positive squares in 8 ways, for example, as 31711061776 + 189499149225 = 178076^2 + 435315^2 .

It is not a de Polignac number, because 221210211001 - 2⁹ = 221210210489 is a prime.

It is a super-2 number, since 2×221210211001² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221210211007) 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, 3622830 + ... + 3683383.

It is an arithmetic number, because the mean of its divisors is an integer number (15880056129).

Almost surely, 2^221210211001 is an apocalyptic number.

It is an amenable number.

221210211001 is a deficient number, since it is larger than the sum of its proper divisors (32870687063).

221210211001 is a wasteful number, since it uses less digits than its factorization.

221210211001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7306380.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 221210211001 its reverse (100112012122), we get a palindrome (321322223123).

The spelling of 221210211001 in words is "two hundred twenty-one billion, two hundred ten million, two hundred eleven thousand, one".