21234201236 has 12 divisors (see below), whose sum is σ = 37181761428. Its totient is φ = 10610840832.

The previous prime is 21234201221. The next prime is 21234201269. The reversal of 21234201236 is 63210243212.

It can be written as a sum of positive squares in 2 ways, for example, as 13761636100 + 7472565136 = 117310^2 + 86444^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1557311 + ... + 1570886.

It is an arithmetic number, because the mean of its divisors is an integer number (3098480119).

Almost surely, 2^21234201236 is an apocalyptic number.

It is an amenable number.

21234201236 is a deficient number, since it is larger than the sum of its proper divisors (15947560192).

21234201236 is a wasteful number, since it uses less digits than its factorization.

21234201236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3129898 (or 3129896 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 21234201236 its reverse (63210243212), we get a palindrome (84444444448).

The spelling of 21234201236 in words is "twenty-one billion, two hundred thirty-four million, two hundred one thousand, two hundred thirty-six".