21800102 has 4 divisors (see below), whose sum is σ = 32700156. Its totient is φ = 10900050.

The previous prime is 21800101. The next prime is 21800131. The reversal of 21800102 is 20100812.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21800101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5450024 + ... + 5450027.

It is an arithmetic number, because the mean of its divisors is an integer number (8175039).

Almost surely, 2^21800102 is an apocalyptic number.

21800102 is a deficient number, since it is larger than the sum of its proper divisors (10900054).

21800102 is a wasteful number, since it uses less digits than its factorization.

21800102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10900053.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 21800102 is about 4669.0579349586. The cubic root of 21800102 is about 279.3526798111.

Adding to 21800102 its reverse (20100812), we get a palindrome (41900914).

The spelling of 21800102 in words is "twenty-one million, eight hundred thousand, one hundred two".