20351845 has 8 divisors (see below), whose sum is σ = 24460920. Its totient is φ = 16255680.

The previous prime is 20351843. The next prime is 20351899. The reversal of 20351845 is 54815302.

It can be written as a sum of positive squares in 4 ways, for example, as 272484 + 20079361 = 522^2 + 4481^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20351845 - 2¹ = 20351843 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20351843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 675 + ... + 6415.

It is an arithmetic number, because the mean of its divisors is an integer number (3057615).

Almost surely, 2^20351845 is an apocalyptic number.

It is an amenable number.

20351845 is a deficient number, since it is larger than the sum of its proper divisors (4109075).

20351845 is an equidigital number, since it uses as much as digits as its factorization.

20351845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6455.

The product of its (nonzero) digits is 4800, while the sum is 28.

The square root of 20351845 is about 4511.3019185153. The cubic root of 20351845 is about 273.0242747449.

The spelling of 20351845 in words is "twenty million, three hundred fifty-one thousand, eight hundred forty-five".