21211001212 has 24 divisors (see below), whose sum is σ = 38947158432. Its totient is φ = 10088337600.

The previous prime is 21211001197. The next prime is 21211001219. The reversal of 21211001212 is 21210011212.

It is a junction number, because it is equal to n+sod(n) for n = 21211001192 and 21211001201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211001219) 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, 620239 + ... + 653542.

It is an arithmetic number, because the mean of its divisors is an integer number (1622798268).

Almost surely, 2^21211001212 is an apocalyptic number.

It is an amenable number.

21211001212 is a deficient number, since it is larger than the sum of its proper divisors (17736157220).

21211001212 is a wasteful number, since it uses less digits than its factorization.

21211001212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1273989 (or 1273987 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21211001212 its reverse (21210011212), we get a palindrome (42421012424).

The spelling of 21211001212 in words is "twenty-one billion, two hundred eleven million, one thousand, two hundred twelve".