21212676 has 18 divisors (see below), whose sum is σ = 53621022. Its totient is φ = 7070880.

The previous prime is 21212663. The next prime is 21212677. The reversal of 21212676 is 67621212.

It can be written as a sum of positive squares in only one way, i.e., 14243076 + 6969600 = 3774^2 + 2640^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (21212677) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 294585 + ... + 294656.

Almost surely, 2^21212676 is an apocalyptic number.

It is an amenable number.

21212676 is an abundant number, since it is smaller than the sum of its proper divisors (32408346).

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

21212676 is a wasteful number, since it uses less digits than its factorization.

21212676 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 589251 (or 589246 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 21212676 is about 4605.7220932227. The cubic root of 21212676 is about 276.8206513655.

Adding to 21212676 its reverse (67621212), we get a palindrome (88833888).

The spelling of 21212676 in words is "twenty-one million, two hundred twelve thousand, six hundred seventy-six".