221201220121 has 8 divisors (see below), whose sum is σ = 252804302784. Its totient is φ = 189598864560.

The previous prime is 221201220113. The next prime is 221201220169. The reversal of 221201220121 is 121022102122.

It is a happy number.

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

It is not a de Polignac number, because 221201220121 - 2³ = 221201220113 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221201220095 and 221201220104.

It is not an unprimeable number, because it can be changed into a prime (221201220181) 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, 896826 + ... + 1116556.

It is an arithmetic number, because the mean of its divisors is an integer number (31600537848).

Almost surely, 2^221201220121 is an apocalyptic number.

It is an amenable number.

221201220121 is a deficient number, since it is larger than the sum of its proper divisors (31603082663).

221201220121 is a wasteful number, since it uses less digits than its factorization.

221201220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 363551.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 221201220121 its reverse (121022102122), we get a palindrome (342223322243).

The spelling of 221201220121 in words is "two hundred twenty-one billion, two hundred one million, two hundred twenty thousand, one hundred twenty-one".