20056709 has 4 divisors (see below), whose sum is σ = 20234316. Its totient is φ = 19879104.

The previous prime is 20056703. The next prime is 20056769. The reversal of 20056709 is 90765002.

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

It can be written as a sum of positive squares in 2 ways, for example, as 280900 + 19775809 = 530^2 + 4447^2 .

It is a cyclic number.

It is not a de Polignac number, because 20056709 - 2⁴ = 20056693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20056703) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 88634 + ... + 88859.

It is an arithmetic number, because the mean of its divisors is an integer number (5058579).

Almost surely, 2^20056709 is an apocalyptic number.

It is an amenable number.

20056709 is a deficient number, since it is larger than the sum of its proper divisors (177607).

20056709 is a wasteful number, since it uses less digits than its factorization.

20056709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177606.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 20056709 is about 4478.4717259351. The cubic root of 20056709 is about 271.6980727405.

The spelling of 20056709 in words is "twenty million, fifty-six thousand, seven hundred nine".