21067039 has 4 divisors (see below), whose sum is σ = 24076624. Its totient is φ = 18057456.

The previous prime is 21067037. The next prime is 21067043. The reversal of 21067039 is 93076012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21067039 - 2¹ = 21067037 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21066998 and 21067016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21067031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1504782 + ... + 1504795.

It is an arithmetic number, because the mean of its divisors is an integer number (6019156).

Almost surely, 2^21067039 is an apocalyptic number.

21067039 is a deficient number, since it is larger than the sum of its proper divisors (3009585).

21067039 is an equidigital number, since it uses as much as digits as its factorization.

21067039 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3009584.

The product of its (nonzero) digits is 2268, while the sum is 28.

The square root of 21067039 is about 4589.8844212028. The cubic root of 21067039 is about 276.1856859761.

The spelling of 21067039 in words is "twenty-one million, sixty-seven thousand, thirty-nine".