20316851 has 4 divisors (see below), whose sum is σ = 20327472. Its totient is φ = 20306232.

The previous prime is 20316841. The next prime is 20316883. The reversal of 20316851 is 15861302.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 15861302 = 2 ⋅7930651.

It is a cyclic number.

It is not a de Polignac number, because 20316851 - 2⁶ = 20316787 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20316851.

It is not an unprimeable number, because it can be changed into a prime (20316841) 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, 1556 + ... + 6561.

It is an arithmetic number, because the mean of its divisors is an integer number (5081868).

Almost surely, 2^20316851 is an apocalyptic number.

20316851 is a deficient number, since it is larger than the sum of its proper divisors (10621).

20316851 is an equidigital number, since it uses as much as digits as its factorization.

20316851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10620.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 20316851 is about 4507.4217685945. The cubic root of 20316851 is about 272.8677010172.

The spelling of 20316851 in words is "twenty million, three hundred sixteen thousand, eight hundred fifty-one".