121221012220 has 48 divisors (see below), whose sum is σ = 317378654208. Its totient is φ = 37783172160.

The previous prime is 121221012217. The next prime is 121221012233. The reversal of 121221012220 is 22210122121.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 121221012194 and 121221012203.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39355932 + ... + 39359011.

It is an arithmetic number, because the mean of its divisors is an integer number (6612055296).

Almost surely, 2^121221012220 is an apocalyptic number.

121221012220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121221012220 is an abundant number, since it is smaller than the sum of its proper divisors (196157641988).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121221012220 is a wasteful number, since it uses less digits than its factorization.

121221012220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78714970 (or 78714968 counting only the distinct ones).

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

Adding to 121221012220 its reverse (22210122121), we get a palindrome (143431134341).

The spelling of 121221012220 in words is "one hundred twenty-one billion, two hundred twenty-one million, twelve thousand, two hundred twenty".