20007689 has 4 divisors (see below), whose sum is σ = 21546756. Its totient is φ = 18468624.

The previous prime is 20007683. The next prime is 20007719. The reversal of 20007689 is 98670002.

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 8952064 + 11055625 = 2992^2 + 3325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20007689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20007683) 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, 769514 + ... + 769539.

It is an arithmetic number, because the mean of its divisors is an integer number (5386689).

Almost surely, 2^20007689 is an apocalyptic number.

It is an amenable number.

20007689 is a deficient number, since it is larger than the sum of its proper divisors (1539067).

20007689 is a wasteful number, since it uses less digits than its factorization.

20007689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1539066.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 20007689 is about 4472.9955287257. The cubic root of 20007689 is about 271.4765424645.

The spelling of 20007689 in words is "twenty million, seven thousand, six hundred eighty-nine".