20442689 has 8 divisors (see below), whose sum is σ = 21560640. Its totient is φ = 19328976.

The previous prime is 20442661. The next prime is 20442691. The reversal of 20442689 is 98624402.

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 20442689 - 2¹⁶ = 20377153 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20442629) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16247 + ... + 17459.

It is an arithmetic number, because the mean of its divisors is an integer number (2695080).

Almost surely, 2^20442689 is an apocalyptic number.

It is an amenable number.

20442689 is a deficient number, since it is larger than the sum of its proper divisors (1117951).

20442689 is a wasteful number, since it uses less digits than its factorization.

20442689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2119.

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 20442689 is about 4521.3591982942. The cubic root of 20442689 is about 273.4299022586.

The spelling of 20442689 in words is "twenty million, four hundred forty-two thousand, six hundred eighty-nine".