21075426 has 12 divisors (see below), whose sum is σ = 45663462. Its totient is φ = 7025136.

The previous prime is 21075421. The next prime is 21075433. The reversal of 21075426 is 62457012.

It can be written as a sum of positive squares in only one way, i.e., 17214201 + 3861225 = 4149^2 + 1965^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21075426.

It is not an unprimeable number, because it can be changed into a prime (21075421) 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, 585411 + ... + 585446.

Almost surely, 2^21075426 is an apocalyptic number.

21075426 is an abundant number, since it is smaller than the sum of its proper divisors (24588036).

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

21075426 is a wasteful number, since it uses less digits than its factorization.

21075426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1170865 (or 1170862 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 21075426 is about 4590.7979698523. The cubic root of 21075426 is about 276.2223318795. Note that the first 3 decimals are identical.

The spelling of 21075426 in words is "twenty-one million, seventy-five thousand, four hundred twenty-six".