20940305 has 8 divisors (see below), whose sum is σ = 25223400. Its totient is φ = 16688896.

The previous prime is 20940289. The next prime is 20940329. The reversal of 20940305 is 50304902.

It can be written as a sum of positive squares in 4 ways, for example, as 529 + 20939776 = 23^2 + 4576^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20940305 - 2⁴ = 20940289 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6440 + ... + 9129.

It is an arithmetic number, because the mean of its divisors is an integer number (3152925).

Almost surely, 2^20940305 is an apocalyptic number.

It is an amenable number.

20940305 is a deficient number, since it is larger than the sum of its proper divisors (4283095).

20940305 is a wasteful number, since it uses less digits than its factorization.

20940305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15843.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 20940305 is about 4576.0578012084. The cubic root of 20940305 is about 275.6307505275.

The spelling of 20940305 in words is "twenty million, nine hundred forty thousand, three hundred five".