2790721 has 2 divisors, whose sum is σ = 2790722. Its totient is φ = 2790720.

The previous prime is 2790707. The next prime is 2790769. The reversal of 2790721 is 1270972.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2772225 + 18496 = 1665^2 + 136^2 .

It is a cyclic number.

It is not a de Polignac number, because 2790721 - 2⁹ = 2790209 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2790721.

It is not a weakly prime, because it can be changed into another prime (2790421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1395360 + 1395361.

It is an arithmetic number, because the mean of its divisors is an integer number (1395361).

2^2790721 is an apocalyptic number.

It is an amenable number.

2790721 is a deficient number, since it is larger than the sum of its proper divisors (1).

2790721 is an equidigital number, since it uses as much as digits as its factorization.

2790721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1764, while the sum is 28.

The square root of 2790721 is about 1670.5451206118. The cubic root of 2790721 is about 140.7901073725.

The spelling of 2790721 in words is "two million, seven hundred ninety thousand, seven hundred twenty-one".