2019961 has 4 divisors (see below), whose sum is σ = 2023924. Its totient is φ = 2016000.

The previous prime is 2019959. The next prime is 2019967. The reversal of 2019961 is 1699102.

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 1610361 + 409600 = 1269^2 + 640^2 .

It is a cyclic number.

It is not a de Polignac number, because 2019961 - 2¹ = 2019959 is a prime.

It is an Ulam number.

It is a Duffinian number.

2019961 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2019967) 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 3 ways as a sum of consecutive naturals, for example, 1080 + ... + 2281.

It is an arithmetic number, because the mean of its divisors is an integer number (505981).

2^2019961 is an apocalyptic number.

It is an amenable number.

2019961 is a deficient number, since it is larger than the sum of its proper divisors (3963).

2019961 is an equidigital number, since it uses as much as digits as its factorization.

2019961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3962.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 2019961 is about 1421.2533201368. The cubic root of 2019961 is about 126.4098729470.

The spelling of 2019961 in words is "two million, nineteen thousand, nine hundred sixty-one".