2158649 has 2 divisors, whose sum is σ = 2158650. Its totient is φ = 2158648.

The previous prime is 2158631. The next prime is 2158679. The reversal of 2158649 is 9468512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1836025 + 322624 = 1355^2 + 568^2 .

It is a cyclic number.

It is not a de Polignac number, because 2158649 - 2⁸ = 2158393 is a prime.

It is a d-powerful number, because it can be written as 2 + 1 + 5³ + 8⁷ + 6⁴ + 4⁵ + 9⁵ .

It is not a weakly prime, because it can be changed into another prime (2158679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1079324 + 1079325.

It is an arithmetic number, because the mean of its divisors is an integer number (1079325).

2^2158649 is an apocalyptic number.

It is an amenable number.

2158649 is a deficient number, since it is larger than the sum of its proper divisors (1).

2158649 is an equidigital number, since it uses as much as digits as its factorization.

2158649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 17280, while the sum is 35.

The square root of 2158649 is about 1469.2341542450. The cubic root of 2158649 is about 129.2391253990.

The spelling of 2158649 in words is "two million, one hundred fifty-eight thousand, six hundred forty-nine".