121220022144 has 64 divisors (see below), whose sum is σ = 346759212240. Its totient is φ = 37298466816.

The previous prime is 121220022109. The next prime is 121220022149. The reversal of 121220022144 is 441220022121.

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 121220022144.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121220022149) 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, 12136437 + ... + 12146420.

Almost surely, 2^121220022144 is an apocalyptic number.

It is an amenable number.

121220022144 is an abundant number, since it is smaller than the sum of its proper divisors (225539190096).

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

121220022144 is a wasteful number, since it uses less digits than its factorization.

121220022144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24282887 (or 24282875 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 121220022144 its reverse (441220022121), we get a palindrome (562440044265).

The spelling of 121220022144 in words is "one hundred twenty-one billion, two hundred twenty million, twenty-two thousand, one hundred forty-four".