21026212 has 48 divisors (see below), whose sum is σ = 40966128. Its totient is φ = 9400320.

The previous prime is 21026197. The next prime is 21026231. The reversal of 21026212 is 21262012.

It can be written as a sum of positive squares in 8 ways, for example, as 287296 + 20738916 = 536^2 + 4554^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 153408 + ... + 153544.

It is an arithmetic number, because the mean of its divisors is an integer number (853461).

Almost surely, 2^21026212 is an apocalyptic number.

It is an amenable number.

21026212 is a deficient number, since it is larger than the sum of its proper divisors (19939916).

21026212 is a wasteful number, since it uses less digits than its factorization.

21026212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256 (or 254 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 21026212 is about 4585.4347667370. The cubic root of 21026212 is about 276.0071586745.

Adding to 21026212 its reverse (21262012), we get a palindrome (42288224).

The spelling of 21026212 in words is "twenty-one million, twenty-six thousand, two hundred twelve".