20765569 has 8 divisors (see below), whose sum is σ = 22908960. Its totient is φ = 18664800.

The previous prime is 20765561. The next prime is 20765599. The reversal of 20765569 is 96556702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20765569 - 2³ = 20765561 is a prime.

It is a super-2 number, since 2×20765569² = 862417711787522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20765561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9627 + ... + 11584.

It is an arithmetic number, because the mean of its divisors is an integer number (2863620).

Almost surely, 2^20765569 is an apocalyptic number.

It is an amenable number.

20765569 is a deficient number, since it is larger than the sum of its proper divisors (2143391).

20765569 is a wasteful number, since it uses less digits than its factorization.

20765569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21311.

The product of its (nonzero) digits is 113400, while the sum is 40.

The square root of 20765569 is about 4556.9253888998. The cubic root of 20765569 is about 274.8619428245.

The spelling of 20765569 in words is "twenty million, seven hundred sixty-five thousand, five hundred sixty-nine".