2819991 has 4 divisors (see below), whose sum is σ = 3759992. Its totient is φ = 1879992.

The previous prime is 2819987. The next prime is 2820001. The reversal of 2819991 is 1999182.

It is a happy number.

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

It is not a de Polignac number, because 2819991 - 2² = 2819987 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2819911) 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, 469996 + ... + 470001.

It is an arithmetic number, because the mean of its divisors is an integer number (939998).

2^2819991 is an apocalyptic number.

2819991 is a deficient number, since it is larger than the sum of its proper divisors (940001).

2819991 is an equidigital number, since it uses as much as digits as its factorization.

2819991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 940000.

The product of its digits is 11664, while the sum is 39.

The square root of 2819991 is about 1679.2828826615. The cubic root of 2819991 is about 141.2806141386.

The spelling of 2819991 in words is "two million, eight hundred nineteen thousand, nine hundred ninety-one".