221001201219978 has 16 divisors (see below), whose sum is σ = 491113780488960. Its totient is φ = 73667067073308.

The previous prime is 221001201219977. The next prime is 221001201220027. The reversal of 221001201219978 is 879912102100122.

221001201219978 is a `hidden beast` number, since 221 + 0 + 0 + 1 + 201 + 219 + 9 + 7 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (221001201219971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2046307418650 + ... + 2046307418757.

It is an arithmetic number, because the mean of its divisors is an integer number (30694611280560).

Almost surely, 2^{221001201219978} is an apocalyptic number.

221001201219978 is an abundant number, since it is smaller than the sum of its proper divisors (270112579268982).

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

221001201219978 is a wasteful number, since it uses less digits than its factorization.

221001201219978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4092614837418 (or 4092614837412 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The spelling of 221001201219978 in words is "two hundred twenty-one trillion, one billion, two hundred one million, two hundred nineteen thousand, nine hundred seventy-eight".