221122402661 has 16 divisors (see below), whose sum is σ = 244616844288. Its totient is φ = 199153468800.

The previous prime is 221122402643. The next prime is 221122402693. The reversal of 221122402661 is 166204221122.

It is a cyclic number.

It is not a de Polignac number, because 221122402661 - 2³⁰ = 220048660837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221122482661) 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, 4164560 + ... + 4217321.

It is an arithmetic number, because the mean of its divisors is an integer number (15288552768).

Almost surely, 2^221122402661 is an apocalyptic number.

It is an amenable number.

221122402661 is a deficient number, since it is larger than the sum of its proper divisors (23494441627).

221122402661 is a wasteful number, since it uses less digits than its factorization.

221122402661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8381972.

The product of its (nonzero) digits is 4608, while the sum is 29.

Adding to 221122402661 its reverse (166204221122), we get a palindrome (387326623783).

The spelling of 221122402661 in words is "two hundred twenty-one billion, one hundred twenty-two million, four hundred two thousand, six hundred sixty-one".