21240226 has 24 divisors (see below), whose sum is σ = 37582380. Its totient is φ = 8975232.

The previous prime is 21240223. The next prime is 21240251. The reversal of 21240226 is 62204212.

It can be written as a sum of positive squares in 2 ways, for example, as 19140625 + 2099601 = 4375^2 + 1449^2 .

It is a super-2 number, since 2×21240226² = 902294401062152, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21240221) 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, 5670 + ... + 8638.

Almost surely, 2^21240226 is an apocalyptic number.

21240226 is a deficient number, since it is larger than the sum of its proper divisors (16342154).

21240226 is a wasteful number, since it uses less digits than its factorization.

21240226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3058 (or 3051 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 21240226 is about 4608.7119675675. The cubic root of 21240226 is about 276.9404399567.

Adding to 21240226 its reverse (62204212), we get a palindrome (83444438).

The spelling of 21240226 in words is "twenty-one million, two hundred forty thousand, two hundred twenty-six".