20873851 has 4 divisors (see below), whose sum is σ = 20942152. Its totient is φ = 20805552.

The previous prime is 20873849. The next prime is 20873861. The reversal of 20873851 is 15837802.

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

It is a cyclic number.

It is not a de Polignac number, because 20873851 - 2¹ = 20873849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20873821) 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, 33690 + ... + 34303.

It is an arithmetic number, because the mean of its divisors is an integer number (5235538).

Almost surely, 2^20873851 is an apocalyptic number.

20873851 is a deficient number, since it is larger than the sum of its proper divisors (68301).

20873851 is an equidigital number, since it uses as much as digits as its factorization.

20873851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68300.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 20873851 is about 4568.7909779284. The cubic root of 20873851 is about 275.3388704076.

The spelling of 20873851 in words is "twenty million, eight hundred seventy-three thousand, eight hundred fifty-one".