2628991 has 4 divisors (see below), whose sum is σ = 2656192. Its totient is φ = 2601792.

The previous prime is 2628979. The next prime is 2629001. The reversal of 2628991 is 1998262.

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

It is a cyclic number.

It is not a de Polignac number, because 2628991 - 2¹⁹ = 2104703 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2628991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2628911) 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, 13455 + ... + 13648.

It is an arithmetic number, because the mean of its divisors is an integer number (664048).

2^2628991 is an apocalyptic number.

2628991 is a deficient number, since it is larger than the sum of its proper divisors (27201).

2628991 is an equidigital number, since it uses as much as digits as its factorization.

2628991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27200.

The product of its digits is 15552, while the sum is 37.

The square root of 2628991 is about 1621.4163561529. The cubic root of 2628991 is about 138.0160836817.

The spelling of 2628991 in words is "two million, six hundred twenty-eight thousand, nine hundred ninety-one".