21203144212 has 24 divisors (see below), whose sum is σ = 37405123560. Its totient is φ = 10516085760.

The previous prime is 21203144203. The next prime is 21203144233. The reversal of 21203144212 is 21244130212.

It can be written as a sum of positive squares in 4 ways, for example, as 641304976 + 20561839236 = 25324^2 + 143394^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 731614 + ... + 760042.

It is an arithmetic number, because the mean of its divisors is an integer number (1558546815).

Almost surely, 2^21203144212 is an apocalyptic number.

It is an amenable number.

21203144212 is a deficient number, since it is larger than the sum of its proper divisors (16201979348).

21203144212 is a wasteful number, since it uses less digits than its factorization.

21203144212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29931 (or 29929 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

Adding to 21203144212 its reverse (21244130212), we get a palindrome (42447274424).

The spelling of 21203144212 in words is "twenty-one billion, two hundred three million, one hundred forty-four thousand, two hundred twelve".