212102109978 has 64 divisors (see below), whose sum is σ = 470189905920. Its totient is φ = 63244684800.

The previous prime is 212102109929. The next prime is 212102109979. The reversal of 212102109978 is 879901201212.

It is not an unprimeable number, because it can be changed into a prime (212102109979) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4082223 + ... + 4133853.

It is an arithmetic number, because the mean of its divisors is an integer number (7346717280).

Almost surely, 2^212102109978 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 212102109978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (235094952960).

212102109978 is an abundant number, since it is smaller than the sum of its proper divisors (258087795942).

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

212102109978 is a wasteful number, since it uses less digits than its factorization.

212102109978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52643.

The product of its (nonzero) digits is 36288, while the sum is 42.

The spelling of 212102109978 in words is "two hundred twelve billion, one hundred two million, one hundred nine thousand, nine hundred seventy-eight".