21110211982 has 4 divisors (see below), whose sum is σ = 31665317976. Its totient is φ = 10555105990.

The previous prime is 21110211973. The next prime is 21110212003. The reversal of 21110211982 is 28911201112.

It is a semiprime because it is the product of two primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21110211982.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5277552994 + ... + 5277552997.

It is an arithmetic number, because the mean of its divisors is an integer number (7916329494).

Almost surely, 2^21110211982 is an apocalyptic number.

21110211982 is a deficient number, since it is larger than the sum of its proper divisors (10555105994).

21110211982 is a wasteful number, since it uses less digits than its factorization.

21110211982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10555105993.

The product of its (nonzero) digits is 576, while the sum is 28.

The spelling of 21110211982 in words is "twenty-one billion, one hundred ten million, two hundred eleven thousand, nine hundred eighty-two".