21002012212 has 12 divisors (see below), whose sum is σ = 36772807680. Its totient is φ = 10495495736.

The previous prime is 21002012209. The next prime is 21002012237. The reversal of 21002012212 is 21221020012.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21002012192 and 21002012201.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1369012 + ... + 1384267.

It is an arithmetic number, because the mean of its divisors is an integer number (3064400640).

Almost surely, 2^21002012212 is an apocalyptic number.

It is an amenable number.

21002012212 is a deficient number, since it is larger than the sum of its proper divisors (15770795468).

21002012212 is a wasteful number, since it uses less digits than its factorization.

21002012212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2755190 (or 2755188 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21002012212 its reverse (21221020012), we get a palindrome (42223032224).

The spelling of 21002012212 in words is "twenty-one billion, two million, twelve thousand, two hundred twelve".