20874985 has 4 divisors (see below), whose sum is σ = 25049988. Its totient is φ = 16699984.

The previous prime is 20874979. The next prime is 20875009. The reversal of 20874985 is 58947802.

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 11209104 + 9665881 = 3348^2 + 3109^2 .

It is a cyclic number.

It is not a de Polignac number, because 20874985 - 2⁹ = 20874473 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2087494 + ... + 2087503.

It is an arithmetic number, because the mean of its divisors is an integer number (6262497).

Almost surely, 2^20874985 is an apocalyptic number.

It is an amenable number.

20874985 is a deficient number, since it is larger than the sum of its proper divisors (4175003).

20874985 is an equidigital number, since it uses as much as digits as its factorization.

20874985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4175002.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 20874985 is about 4568.9150790970. The cubic root of 20874985 is about 275.3438563687.

The spelling of 20874985 in words is "twenty million, eight hundred seventy-four thousand, nine hundred eighty-five".