20874281 has 4 divisors (see below), whose sum is σ = 20917632. Its totient is φ = 20830932.

The previous prime is 20874257. The next prime is 20874299. The reversal of 20874281 is 18247802.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18247802 = 2 ⋅9123901.

It is a cyclic number.

It is not a de Polignac number, because 20874281 - 2¹⁰ = 20873257 is a prime.

It is a super-2 number, since 2×20874281² = 871471214533922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20874211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20945 + ... + 21918.

It is an arithmetic number, because the mean of its divisors is an integer number (5229408).

Almost surely, 2^20874281 is an apocalyptic number.

It is an amenable number.

20874281 is a deficient number, since it is larger than the sum of its proper divisors (43351).

20874281 is an equidigital number, since it uses as much as digits as its factorization.

20874281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43350.

The product of its (nonzero) digits is 7168, while the sum is 32.

The square root of 20874281 is about 4568.8380360875. The cubic root of 20874281 is about 275.3407610491.

The spelling of 20874281 in words is "twenty million, eight hundred seventy-four thousand, two hundred eighty-one".