20285137 has 4 divisors (see below), whose sum is σ = 20307636. Its totient is φ = 20262640.

The previous prime is 20285099. The next prime is 20285263. The reversal of 20285137 is 73158202.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6713281 + 13571856 = 2591^2 + 3684^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20285137 is a prime.

It is a super-2 number, since 2×20285137² = 822973566217538, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20285737) 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, 9838 + ... + 11719.

It is an arithmetic number, because the mean of its divisors is an integer number (5076909).

Almost surely, 2^20285137 is an apocalyptic number.

It is an amenable number.

20285137 is a deficient number, since it is larger than the sum of its proper divisors (22499).

20285137 is an equidigital number, since it uses as much as digits as its factorization.

20285137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22498.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 20285137 is about 4503.9024190140. The cubic root of 20285137 is about 272.7256476233.

The spelling of 20285137 in words is "twenty million, two hundred eighty-five thousand, one hundred thirty-seven".