2578991 has 2 divisors, whose sum is σ = 2578992. Its totient is φ = 2578990.

The previous prime is 2578987. The next prime is 2578993. The reversal of 2578991 is 1998752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2578991 - 2² = 2578987 is a prime.

It is a Sophie Germain prime.

Together with 2578993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2578993) 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 as a sum of consecutive naturals, namely, 1289495 + 1289496.

It is an arithmetic number, because the mean of its divisors is an integer number (1289496).

2^2578991 is an apocalyptic number.

2578991 is a deficient number, since it is larger than the sum of its proper divisors (1).

2578991 is an equidigital number, since it uses as much as digits as its factorization.

2578991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360, while the sum is 41.

The square root of 2578991 is about 1605.9237217253. The cubic root of 2578991 is about 137.1355151183.

The spelling of 2578991 in words is "two million, five hundred seventy-eight thousand, nine hundred ninety-one".