21201211131212 has 36 divisors (see below), whose sum is σ = 43194898812240. Its totient is φ = 9078803776224.

The previous prime is 21201211131179. The next prime is 21201211131257. The reversal of 21201211131212 is 21213111210212.

It is a super-2 number, since 2×21201211131212² (a number of 27 digits) contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 43983287 + ... + 44462702.

It is an arithmetic number, because the mean of its divisors is an integer number (1199858300340).

Almost surely, 2^{21201211131212} is an apocalyptic number.

It is an amenable number.

21201211131212 is an abundant number, since it is smaller than the sum of its proper divisors (21993687681028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21201211131212 is a wasteful number, since it uses less digits than its factorization.

21201211131212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88447230 (or 88447221 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 20.

Adding to 21201211131212 its reverse (21213111210212), we get a palindrome (42414322341424).

The spelling of 21201211131212 in words is "twenty-one trillion, two hundred one billion, two hundred eleven million, one hundred thirty-one thousand, two hundred twelve".