21001210212 has 36 divisors (see below), whose sum is σ = 50363058480. Its totient is φ = 6811197984.

The previous prime is 21001210211. The next prime is 21001210229. The reversal of 21001210212 is 21201210012.

It is a super-2 number, since 2×21001210212² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21001210211) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 622762 + ... + 655617.

Almost surely, 2^21001210212 is an apocalyptic number.

It is an amenable number.

21001210212 is an abundant number, since it is smaller than the sum of its proper divisors (29361848268).

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

21001210212 is a wasteful number, since it uses less digits than its factorization.

21001210212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1278460 (or 1278421 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21001210212 its reverse (21201210012), we get a palindrome (42202420224).

The spelling of 21001210212 in words is "twenty-one billion, one million, two hundred ten thousand, two hundred twelve".