220121209978 has 16 divisors (see below), whose sum is σ = 336446098560. Its totient is φ = 107992117296.

The previous prime is 220121209969. The next prime is 220121210011. The reversal of 220121209978 is 879902121022.

It is a happy number.

220121209978 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4879150 + ... + 4924057.

It is an arithmetic number, because the mean of its divisors is an integer number (21027881160).

Almost surely, 2^220121209978 is an apocalyptic number.

220121209978 is a deficient number, since it is larger than the sum of its proper divisors (116324888582).

220121209978 is a wasteful number, since it uses less digits than its factorization.

220121209978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9803421.

The product of its (nonzero) digits is 72576, while the sum is 43.

The spelling of 220121209978 in words is "two hundred twenty billion, one hundred twenty-one million, two hundred nine thousand, nine hundred seventy-eight".