21816802 has 8 divisors (see below), whose sum is σ = 37400256. Its totient is φ = 9350052.

The previous prime is 21816757. The next prime is 21816803. The reversal of 21816802 is 20861812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21816803) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 779158 + ... + 779185.

It is an arithmetic number, because the mean of its divisors is an integer number (4675032).

Almost surely, 2^21816802 is an apocalyptic number.

21816802 is a deficient number, since it is larger than the sum of its proper divisors (15583454).

21816802 is a wasteful number, since it uses less digits than its factorization.

21816802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1558352.

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 21816802 is about 4670.8459619217. The cubic root of 21816802 is about 279.4239944468.

It can be divided in two parts, 218 and 16802, that added together give a triangular number (17020 = T₁₈₄).

The spelling of 21816802 in words is "twenty-one million, eight hundred sixteen thousand, eight hundred two".