20245281 has 12 divisors (see below), whose sum is σ = 31401072. Its totient is φ = 11568648.

The previous prime is 20245273. The next prime is 20245289. The reversal of 20245281 is 18254202.

It is an interprime number because it is at equal distance from previous prime (20245273) and next prime (20245289).

It is not a de Polignac number, because 20245281 - 2³ = 20245273 is a prime.

It is a super-2 number, since 2×20245281² = 819742805537922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20245289) 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, 68715 + ... + 69008.

It is an arithmetic number, because the mean of its divisors is an integer number (2616756).

Almost surely, 2^20245281 is an apocalyptic number.

20245281 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20245281 is a deficient number, since it is larger than the sum of its proper divisors (11155791).

20245281 is a wasteful number, since it uses less digits than its factorization.

20245281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137740 (or 137733 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 24.

The square root of 20245281 is about 4499.4756361158. The cubic root of 20245281 is about 272.5469144600.

Adding to 20245281 its reverse (18254202), we get a palindrome (38499483).

The spelling of 20245281 in words is "twenty million, two hundred forty-five thousand, two hundred eighty-one".