21212111982 has 16 divisors (see below), whose sum is σ = 42444460800. Its totient is φ = 7067331192.

The previous prime is 21212111969. The next prime is 21212112007. The reversal of 21212111982 is 28911121212.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 829558 + ... + 854745.

It is an arithmetic number, because the mean of its divisors is an integer number (2652778800).

Almost surely, 2^21212111982 is an apocalyptic number.

21212111982 is an abundant number, since it is smaller than the sum of its proper divisors (21232348818).

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

21212111982 is a wasteful number, since it uses less digits than its factorization.

21212111982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1686407.

The product of its digits is 1152, while the sum is 30.

The spelling of 21212111982 in words is "twenty-one billion, two hundred twelve million, one hundred eleven thousand, nine hundred eighty-two".