121121012221 has 12 divisors (see below), whose sum is σ = 133344084832. Its totient is φ = 109935441000.

The previous prime is 121121012209. The next prime is 121121012231. The reversal of 121121012221 is 122210121121.

It is not a de Polignac number, because 121121012221 - 2¹¹ = 121121010173 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121121012195 and 121121012204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121121012231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 716835 + ... + 869536.

Almost surely, 2^121121012221 is an apocalyptic number.

121121012221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121121012221 is a deficient number, since it is larger than the sum of its proper divisors (12223072611).

121121012221 is a wasteful number, since it uses less digits than its factorization.

121121012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1587024 (or 1587013 counting only the distinct ones).

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

Adding to 121121012221 its reverse (122210121121), we get a palindrome (243331133342).

The spelling of 121121012221 in words is "one hundred twenty-one billion, one hundred twenty-one million, twelve thousand, two hundred twenty-one".