21240204202 has 16 divisors (see below), whose sum is σ = 36416983680. Its totient is φ = 9101643408.

The previous prime is 21240204149. The next prime is 21240204229. The reversal of 21240204202 is 20240204212.

It is a super-2 number, since 2×21240204202² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21240204202.

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, 3502 + ... + 206137.

It is an arithmetic number, because the mean of its divisors is an integer number (2276061480).

Almost surely, 2^21240204202 is an apocalyptic number.

21240204202 is a deficient number, since it is larger than the sum of its proper divisors (15176779478).

21240204202 is a wasteful number, since it uses less digits than its factorization.

21240204202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 216885.

The product of its (nonzero) digits is 512, while the sum is 19.

Adding to 21240204202 its reverse (20240204212), we get a palindrome (41480408414).

The spelling of 21240204202 in words is "twenty-one billion, two hundred forty million, two hundred four thousand, two hundred two".