2391861 has 4 divisors (see below), whose sum is σ = 3189152. Its totient is φ = 1594572.

The previous prime is 2391859. The next prime is 2391863. The reversal of 2391861 is 1681932.

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 an interprime number because it is at equal distance from previous prime (2391859) and next prime (2391863).

It is not a de Polignac number, because 2391861 - 2¹ = 2391859 is a prime.

It is a D-number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2391863) 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, 398641 + ... + 398646.

It is an arithmetic number, because the mean of its divisors is an integer number (797288).

2^2391861 is an apocalyptic number.

It is an amenable number.

2391861 is a deficient number, since it is larger than the sum of its proper divisors (797291).

2391861 is an equidigital number, since it uses as much as digits as its factorization.

2391861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 797290.

The product of its digits is 2592, while the sum is 30.

The square root of 2391861 is about 1546.5642566670. The cubic root of 2391861 is about 133.7350709747.

The spelling of 2391861 in words is "two million, three hundred ninety-one thousand, eight hundred sixty-one".