21202111211212 has 24 divisors (see below), whose sum is σ = 37161410755392. Its totient is φ = 10584568117200.

The previous prime is 21202111211173. The next prime is 21202111211219. The reversal of 21202111211212 is 21211211120212.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21202111211212.

It is not an unprimeable number, because it can be changed into a prime (21202111211219) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30061287 + ... + 30758497.

It is an arithmetic number, because the mean of its divisors is an integer number (1548392114808).

Almost surely, 2^{21202111211212} is an apocalyptic number.

It is an amenable number.

21202111211212 is a deficient number, since it is larger than the sum of its proper divisors (15959299544180).

21202111211212 is a wasteful number, since it uses less digits than its factorization.

21202111211212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 709029 (or 709027 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21202111211212 its reverse (21211211120212), we get a palindrome (42413322331424).

The spelling of 21202111211212 in words is "twenty-one trillion, two hundred two billion, one hundred eleven million, two hundred eleven thousand, two hundred twelve".