21203210234 has 4 divisors (see below), whose sum is σ = 31804815354. Its totient is φ = 10601605116.

The previous prime is 21203210233. The next prime is 21203210297. The reversal of 21203210234 is 43201230212.

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

It can be written as a sum of positive squares in only one way, i.e., 16384768009 + 4818442225 = 128003^2 + 69415^2 .

It is a super-2 number, since 2×21203210234² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21203210233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5300802557 + ... + 5300802560.

Almost surely, 2^21203210234 is an apocalyptic number.

21203210234 is a deficient number, since it is larger than the sum of its proper divisors (10601605120).

21203210234 is a wasteful number, since it uses less digits than its factorization.

21203210234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10601605119.

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21203210234 its reverse (43201230212), we get a palindrome (64404440446).

The spelling of 21203210234 in words is "twenty-one billion, two hundred three million, two hundred ten thousand, two hundred thirty-four".