2019851 has 2 divisors, whose sum is σ = 2019852. Its totient is φ = 2019850.

The previous prime is 2019847. The next prime is 2019859. The reversal of 2019851 is 1589102.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2019851 - 2² = 2019847 is a prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 2019851.

It is not a weakly prime, because it can be changed into another prime (2019859) 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 as a sum of consecutive naturals, namely, 1009925 + 1009926.

It is an arithmetic number, because the mean of its divisors is an integer number (1009926).

2^2019851 is an apocalyptic number.

2019851 is a deficient number, since it is larger than the sum of its proper divisors (1).

2019851 is an equidigital number, since it uses as much as digits as its factorization.

2019851 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 26.

The square root of 2019851 is about 1421.2146213715. The cubic root of 2019851 is about 126.4075782924.

The spelling of 2019851 in words is "two million, nineteen thousand, eight hundred fifty-one".