21240201212 has 6 divisors (see below), whose sum is σ = 37170352128. Its totient is φ = 10620100604.

The previous prime is 21240201187. The next prime is 21240201247. The reversal of 21240201212 is 21210204212.

It is a super-2 number, since 2×21240201212² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2655025148 + ... + 2655025155.

It is an arithmetic number, because the mean of its divisors is an integer number (6195058688).

Almost surely, 2^21240201212 is an apocalyptic number.

It is an amenable number.

21240201212 is a deficient number, since it is larger than the sum of its proper divisors (15930150916).

21240201212 is a wasteful number, since it uses less digits than its factorization.

21240201212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5310050307 (or 5310050305 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21240201212 its reverse (21210204212), we get a palindrome (42450405424).

The spelling of 21240201212 in words is "twenty-one billion, two hundred forty million, two hundred one thousand, two hundred twelve".