21110984 has 8 divisors (see below), whose sum is σ = 39583110. Its totient is φ = 10555488.

The previous prime is 21110981. The next prime is 21110989. The reversal of 21110984 is 48901112.

It can be written as a sum of positive squares in only one way, i.e., 20340100 + 770884 = 4510^2 + 878^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (21110981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1319429 + ... + 1319444.

Almost surely, 2^21110984 is an apocalyptic number.

It is an amenable number.

21110984 is a deficient number, since it is larger than the sum of its proper divisors (18472126).

21110984 is a wasteful number, since it uses less digits than its factorization.

21110984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2638879 (or 2638875 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 26.

The square root of 21110984 is about 4594.6690849288. The cubic root of 21110984 is about 276.3775900314.

The spelling of 21110984 in words is "twenty-one million, one hundred ten thousand, nine hundred eighty-four".