221611002166 has 16 divisors (see below), whose sum is σ = 337442716656. Its totient is φ = 109130731776.

The previous prime is 221611002131. The next prime is 221611002199. The reversal of 221611002166 is 661200116122.

It is a super-2 number, since 2×221611002166² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

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, 553690 + ... + 865906.

It is an arithmetic number, because the mean of its divisors is an integer number (21090169791).

Almost surely, 2^221611002166 is an apocalyptic number.

221611002166 is a deficient number, since it is larger than the sum of its proper divisors (115831714490).

221611002166 is a wasteful number, since it uses less digits than its factorization.

221611002166 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317583.

The product of its (nonzero) digits is 1728, while the sum is 28.

Adding to 221611002166 its reverse (661200116122), we get a palindrome (882811118288).

The spelling of 221611002166 in words is "two hundred twenty-one billion, six hundred eleven million, two thousand, one hundred sixty-six".