12122121021978 has 64 divisors (see below), whose sum is σ = 27604680228864. Its totient is φ = 3512831784000.

The previous prime is 12122121021949. The next prime is 12122121021979. The reversal of 12122121021978 is 87912012122121.

It is a happy number.

12122121021978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (12122121021979) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5531143 + ... + 7405253.

It is an arithmetic number, because the mean of its divisors is an integer number (431323128576).

Almost surely, 2^{12122121021978} is an apocalyptic number.

12122121021978 is an abundant number, since it is smaller than the sum of its proper divisors (15482559206886).

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

12122121021978 is a wasteful number, since it uses less digits than its factorization.

12122121021978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1878411.

The product of its (nonzero) digits is 16128, while the sum is 39.

The spelling of 12122121021978 in words is "twelve trillion, one hundred twenty-two billion, one hundred twenty-one million, twenty-one thousand, nine hundred seventy-eight".