221121021121 has 24 divisors (see below), whose sum is σ = 298521042624. Its totient is φ = 159048077760.

The previous prime is 221121021083. The next prime is 221121021131. The reversal of 221121021121 is 121120121122.

It is not a de Polignac number, because 221121021121 - 2¹³ = 221121012929 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221121021095 and 221121021104.

It is not an unprimeable number, because it can be changed into a prime (221121021131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8483146 + ... + 8509171.

It is an arithmetic number, because the mean of its divisors is an integer number (12438376776).

Almost surely, 2^221121021121 is an apocalyptic number.

It is an amenable number.

221121021121 is a deficient number, since it is larger than the sum of its proper divisors (77400021503).

221121021121 is a wasteful number, since it uses less digits than its factorization.

221121021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16992361 (or 16992348 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 221121021121 its reverse (121120121122), we get a palindrome (342241142243).

The spelling of 221121021121 in words is "two hundred twenty-one billion, one hundred twenty-one million, twenty-one thousand, one hundred twenty-one".