2158261 has 4 divisors (see below), whose sum is σ = 2466592. Its totient is φ = 1849932.

The previous prime is 2158259. The next prime is 2158291. The reversal of 2158261 is 1628512.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2158261 - 2¹ = 2158259 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2158231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 154155 + ... + 154168.

It is an arithmetic number, because the mean of its divisors is an integer number (616648).

2^2158261 is an apocalyptic number.

It is an amenable number.

2158261 is a deficient number, since it is larger than the sum of its proper divisors (308331).

2158261 is an equidigital number, since it uses as much as digits as its factorization.

2158261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308330.

The product of its digits is 960, while the sum is 25.

The square root of 2158261 is about 1469.1021067305. The cubic root of 2158261 is about 129.2313816999.

The spelling of 2158261 in words is "two million, one hundred fifty-eight thousand, two hundred sixty-one".