20578869 has 12 divisors (see below), whose sum is σ = 29899116. Its totient is φ = 13638912.

The previous prime is 20578861. The next prime is 20578889. The reversal of 20578869 is 96887502.

It can be written as a sum of positive squares in 2 ways, for example, as 14152644 + 6426225 = 3762^2 + 2535^2 .

It is not a de Polignac number, because 20578869 - 2³ = 20578861 is a prime.

It is a super-2 number, since 2×20578869² = 846979698638322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20578861) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5052 + ... + 8165.

It is an arithmetic number, because the mean of its divisors is an integer number (2491593).

Almost surely, 2^20578869 is an apocalyptic number.

It is an amenable number.

20578869 is a deficient number, since it is larger than the sum of its proper divisors (9320247).

20578869 is a wasteful number, since it uses less digits than its factorization.

20578869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13396 (or 13393 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The square root of 20578869 is about 4536.3938321094. The cubic root of 20578869 is about 274.0357147045.

The spelling of 20578869 in words is "twenty million, five hundred seventy-eight thousand, eight hundred sixty-nine".