20288689 has 4 divisors (see below), whose sum is σ = 20301424. Its totient is φ = 20275956.

The previous prime is 20288687. The next prime is 20288693. The reversal of 20288689 is 98688202.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 98688202 = 2 ⋅49344101.

It is a cyclic number.

It is not a de Polignac number, because 20288689 - 2¹ = 20288687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20288687) 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, 3567 + ... + 7300.

It is an arithmetic number, because the mean of its divisors is an integer number (5075356).

Almost surely, 2^20288689 is an apocalyptic number.

It is an amenable number.

20288689 is a deficient number, since it is larger than the sum of its proper divisors (12735).

20288689 is a wasteful number, since it uses less digits than its factorization.

20288689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12734.

The product of its (nonzero) digits is 110592, while the sum is 43.

The square root of 20288689 is about 4504.2967264602. The cubic root of 20288689 is about 272.7415651062.

The spelling of 20288689 in words is "twenty million, two hundred eighty-eight thousand, six hundred eighty-nine".