2078991 has 6 divisors (see below), whose sum is σ = 3003000. Its totient is φ = 1385988.

The previous prime is 2078977. The next prime is 2079013. The reversal of 2078991 is 1998702.

It is a happy number.

It is not a de Polignac number, because 2078991 - 2⁵ = 2078959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2078971) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 115491 + ... + 115508.

It is an arithmetic number, because the mean of its divisors is an integer number (500500).

2^2078991 is an apocalyptic number.

2078991 is a deficient number, since it is larger than the sum of its proper divisors (924009).

2078991 is a wasteful number, since it uses less digits than its factorization.

2078991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231005 (or 231002 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 36.

The square root of 2078991 is about 1441.8706599415. The cubic root of 2078991 is about 127.6294417834.

The spelling of 2078991 in words is "two million, seventy-eight thousand, nine hundred ninety-one".