20709611 has 4 divisors (see below), whose sum is σ = 22302672. Its totient is φ = 19116552.

The previous prime is 20709607. The next prime is 20709629. The reversal of 20709611 is 11690702.

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

It is not a de Polignac number, because 20709611 - 2² = 20709607 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20709641) 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 3 ways as a sum of consecutive naturals, for example, 796511 + ... + 796536.

It is an arithmetic number, because the mean of its divisors is an integer number (5575668).

Almost surely, 2^20709611 is an apocalyptic number.

20709611 is a deficient number, since it is larger than the sum of its proper divisors (1593061).

20709611 is a wasteful number, since it uses less digits than its factorization.

20709611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1593060.

The product of its (nonzero) digits is 756, while the sum is 26.

The square root of 20709611 is about 4550.7813614807. The cubic root of 20709611 is about 274.6148260540.

The spelling of 20709611 in words is "twenty million, seven hundred nine thousand, six hundred eleven".