20287285 has 8 divisors (see below), whose sum is σ = 25002936. Its totient is φ = 15791040.

The previous prime is 20287277. The next prime is 20287291. The reversal of 20287285 is 58278202.

It can be written as a sum of positive squares in 4 ways, for example, as 12680721 + 7606564 = 3561^2 + 2758^2 .

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

It is not a de Polignac number, because 20287285 - 2³ = 20287277 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20287285.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54646 + ... + 55015.

It is an arithmetic number, because the mean of its divisors is an integer number (3125367).

Almost surely, 2^20287285 is an apocalyptic number.

It is an amenable number.

20287285 is a deficient number, since it is larger than the sum of its proper divisors (4715651).

20287285 is a wasteful number, since it uses less digits than its factorization.

20287285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109703.

The product of its (nonzero) digits is 17920, while the sum is 34.

The square root of 20287285 is about 4504.1408725749. The cubic root of 20287285 is about 272.7352736205.

The spelling of 20287285 in words is "twenty million, two hundred eighty-seven thousand, two hundred eighty-five".