21556274 has 12 divisors (see below), whose sum is σ = 33236154. Its totient is φ = 10485504.

The previous prime is 21556273. The next prime is 21556321. The reversal of 21556274 is 47265512.

It can be written as a sum of positive squares in 3 ways, for example, as 20313049 + 1243225 = 4507^2 + 1115^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21556274.

It is not an unprimeable number, because it can be changed into a prime (21556273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1199 + ... + 6674.

Almost surely, 2^21556274 is an apocalyptic number.

21556274 is a deficient number, since it is larger than the sum of its proper divisors (11679880).

21556274 is an equidigital number, since it uses as much as digits as its factorization.

21556274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7949 (or 7912 counting only the distinct ones).

The product of its digits is 16800, while the sum is 32.

The square root of 21556274 is about 4642.8734637076. The cubic root of 21556274 is about 278.3072788867.

The spelling of 21556274 in words is "twenty-one million, five hundred fifty-six thousand, two hundred seventy-four".